However, the most amazing feature of water is its ability to dissolve other substances. The ability of substances to dissolve depends on their dielectric constant. The higher it is, the more the substance is capable of dissolving others. So, for water, this value is 9 times higher than for air or vacuum. Therefore, fresh or clean waters are practically not found in nature. Something is always dissolved in the earth's water. These can be gases, molecules or ions of chemical elements. It is believed that all the elements of the table of the periodic table of elements can be dissolved in the waters of the oceans, at least today more than 80 of them have been discovered.
Water hardness is understood as a property of natural water, determined by the presence in it of mainly dissolved salts of calcium and magnesium. Water hardness is divided into carbonate(presence of magnesium and calcium bicarbonates) and non-carbonate (presence of chlorides or sulfates of calcium and magnesium). The sum of carbonate and non-carbonate hardness determines overall hardness.
The need to eliminate the hardness of water is caused primarily by an undesirable effect due to its properties.
Thermal impact on hard water leads to the formation of scale on the walls of metal structures (steam boilers, pipes, etc.). This phenomenon is associated with additional energy costs, since scale is a poor conductor of heat. In hard water, corrosion processes occur much faster.
Water hardness is expressed in millimole equivalents of a substance per 1 liter of water - mmol-equiv / l. 1 mmol-eq of calcium or magnesium hardness corresponds to the content of 20.4 mg Ca 2+ and 12.11 mg Mg 2+ in 1 liter of water.
Water hardness is calculated by the formula:
where m is the mass of a substance that determines the hardness of water or is used to eliminate water hardness, mg;
Me- molar mass of equivalents of this substance, g / mol;
V- volume of water, l.
Carbonate hardness is called temporal, because for a long time boiling water with such rigidity, bicarbonate decomposes:
Ca (HCO 3) 2 → CaCO 3 ↓ + CO 2 + H 2 0
M g (HCO 3) 2 → M g (OH) 2 ↓ + 2CO 2
The hardness of water, due to the presence of chlorides or sulfates of magnesium and calcium, is called constant. Permanent hardness can be removed chemically, for example by adding calcium carbonate or calcium hydroxide:
CaS0 4 (p) + Na 2 CO 3 (p) \u003d CaCO e (t) ↓ + Na 2 SO 4 (p)
Ca (HCO 3) 2 (p) + Ca (OH) 2 (p) \u003d 2CaCO 3 (t) ↓ + 2H 2 O
M g SO 4 (p) + Ca (OH) 2 (p) \u003d Mg (OH) 2 (t) ↓ + CaSO 4 (p)
Sodium phosphates, borax, potassium carbonate and other salts are also used to remove Ca 2+ and Mg 2+ ions.
Natural water always avenges differences in its salt, like a stone for the hardness of water. They distinguish the time-hardness of water, as it is coated with calcium and magnesium hydrocarbonates (Ca (HCO 3) 2, Mg (HCO 3) 2). (СаСО 3 , MgСО 3), if they fall into a siege, scale up.
Permanent hardness of water is accumulated by chlorides and sulfates of calcium and magnesium (CaCl 2, CaSO 4, MgCl 2, MgSO 4). Tsya hardness of water is not used by boiling and it is necessary to vicorate chemical reagents for її usunennya.
Timchasov and post-yna hardness is the total hardness of water, as it is characterized by a total concentration of calcium and magnesium ions in milligram-equivalent per 1 kg of water (mg-eq / kg). Mіlіgram-equivalence - the whole quantity of speech, like it shows the atomic mass. So, 1 mg-eq/kg gives 0.02 mg Ca and 0.012 mg magnesium per 1 kg of water. To ensure the long-term and trouble-free operation of modern ship steam-power installations, it is necessary to stop a number of entries that are related to the stoppage of various chemical reagents. Reagents are brought up to them to improve the quality of boiler and life waters and regulate the internal-boiler physical and chemical processes.
Raise the concentration of salts in the boiler water to bring to scale, as a result of which more heat is carried out, overheating of the boiler occurs, which can lead to vibuha. Under the influence of water, steam and steam-and-water sums of metal on the surface of the heating of the boiler, it causes mild crystal corrosion, such metal takes its shape and expands, but at impact it collapses. It is possible to detect this type of corrosion in a timely manner only with the help of ultrasonic and magnetoscopic flaw detectors.
09/18/2018 Grade 10 lesson No. 3
Topic: Inorganic substances of the cell
Goals: to study the chemical composition of the cell, to identify the role of inorganic substances in the cell.
Tasks:
educational: show the variety of chemical elements and compounds that make up living organisms, their significance in life processes;
developing: to continue the formation of skills and abilities of independent work with a textbook, the ability to highlight the main thing, to formulate conclusions;
educational: development of communication skills.
Equipment: presentation, table by D.I. Mendeleev, textbook.
During the classes:
I .orgmoment
II . Checking homework
Conversation on questions (slide 1)
Who first introduced the concept of "cell"?
Who is the creator of the cell theory?
What contribution to the creation of cell theory did Rudolf Virchow and Karl Baer make?
What methods of studying cells exist?
For which representatives of the organic world do the concepts of "cell" and "organism" coincide?
III .Motivation (slide 2)
There is nothing else in nature, neither here nor there, in the cosmic depths:
everything - from small grains of sand to planets - consists of the same elements.
Like a formula, like a schedule, the labor structure of the strict Mendeleev system.
A living world is going on around you, enter it, breathe it in, touch it with your hands.
(Schipachev "Reading Mendeleev")
Think about what this poem is about. How does it relate to today's lesson? Try to formulate the topic of the lesson and set goals for the lesson.
Recording the topic of the lesson (slide 3)
IV . Learning new material
Remember the chemical composition of the cell from the 8th grade biology course and reproduce this diagram (orally) (slide 4)
Does this scheme fully reflect the chemical composition of the cell?
What are substances made of? (from chemical elements).
It means that it is more correct to depict the proposed scheme in a different way (slide 5)
What do we include in the first group? To the second group?
Independent work with a textbook (p. 2 L.N. Sukhorukova, V.S. Kuchmenko “Biology 10-11 grades). Find answers to questions:
What are the chemical elements that make up the cells of living organisms?
How are they classified?
Give examples of each group.
The cell contains approximately 80 chemical elements of the Mendeleev system. All these elements are also found in inanimate nature (slide 6).
What are the similarities between living and non-living things?
There are different amounts of substances in cells (slide 7).
They are classified into 3 groups (slide 8).
Their examples and meaning (slides 9-23).
What inorganic substances are found in cells?
Let's work in groups. The first group will study and prepare a story for us about the mineral salts that make up the cells, and the second about water (about their role in the cell).
The story of the representative of the 2nd group.
Antoine de Saint-Exupery (slide 28) said:
Water - you don't have
no taste, no color, no smell.
You are enjoyed
not knowing what you are...
You are life itself!
What are your thoughts on this?
The properties of water are unusual (slides 29-31). What do they depend on? (from the structure of the water molecule). Let's recall their chemistry course the structure of the water molecule (slide 32).
Properties of water (slide 32-34)
The value of water (slide 35 -39)
V . Consolidation of the studied material
Test "Inorganic substances of the cell" (slide 40-49)
1. What chemical elements contained in the cell are classified as macronutrients?
a ) S, Na, Ca, K; b) O, H, C, N; c) Ni, Cu, I, Br.
2. What are the functions of water in a cell?
a) Transfer of hereditary information;
b) environment for chemical reactions;
c) source of energy.
3. Hydrophobic substances include:
a) salt; b) sugar; c) fats.
4. What ions are part of hemoglobin?
a) Mg2+; b) Fe2+; c) Zn2+.
5. Water is the basis of life, because she is:
a) can be in three states (liquid, solid and gaseous);
b) is a solvent that provides both the influx of substances into the cell and the removal of metabolic products from it;
c) cools the surface during evaporation.
6. Substances that are highly soluble in water are called:
a) hydrophilic; b) hydrophobic; c) amphiphilic.
7. Water has the ability to dissolve substances, since its molecules:
A) polar B) have small molecules;
C) contain atoms connected by an ionic bond; D) form hydrogen bonds with each other
8. The main function of mineral salts in the cell is to maintain:
A) diffuseness; B) buffering; B) osmosis
9. What chemical bonds form between water molecules:
A) covalent; B) hydrophobic; B) hydrogen
10. A water molecule that carries a positive charge at one end and a negative charge at the other is called: A) a dipole; B) dimol; B) dirol
VI . Homework (slide 50)
P. 2, answer questions.
The ability of water to dissolve mineral and organic substances (to be mineralized) is of extremely important geological and hydrogeological significance.
The solubility of various compounds in water is very diverse. The most soluble are some chloride, nitrate and carbonate salts of potassium, sodium and magnesium chloride. The maximum saturation of water with these salts can reach 50% by weight. Slightly soluble (medium solubility) sulfate and even less carbonic salts of calcium and magnesium. Their solubility fluctuates within 0.10-0.001%. Finally, silicates and some other mineral compounds are soluble in such a small amount that practically their solubility can be taken equal to zero. The solubility of salts increases with increasing temperature (there are rare exceptions to this rule) (see Fig. 13). The solubility of gases under this condition decreases. Natural water is always mineralized.
It should be noted that the presence of some substances in solution can either promote or prevent the dissolution of others. So, for example, if there is already carbon dioxide in the water in solution, then the solubility of lime carbonate (limestone, chalk) in such water increases almost three times, and the solubility of calcium sulfate does not change. AvailabilityNaCl increases solubility CaSO 4 in water almost four times, and the presence of magnesium sulfate reduces its solubility to zero. In natural water, limiting saturations with salts and gases are rare.
C0 dissolved in water 2 or salts like R 2 C0 3 contribute to the decomposition of aluminosilicates
K 2 OAl 2 0 3 6 Si0 2 + C0 2 + 10H 2 0 \u003d K 2 C0 3 + 4 Si (OH) 4 + 2 H 2 O Al 2 0 3 2 Si0 2.
Orthoclase Kaolin
|
salt |
Temperature, °C |
|
|
KS1 |
0,29 |
0,60 |
|
NaCl |
0,35 |
0,40 |
|
K 2 S0 4 |
0,10 |
0,26 |
|
Na 2 S0 4 |
0,05 |
0.42 (50°—0.50) |
|
KN0 3 |
0,13 |
2,36 |
|
CaCO3 |
0,00018 |
|
|
FeC0 3 |
0,0007 |
|
|
MnC0 3 |
0,0005 |
|
|
CaSO 4 |
0,0019 |
0.0017 (40°—0.00) |
|
FeS0 4 |
3,30 |
|
|
Mg(OH)2 |
0,0002 |
Insoluble |
|
MgSO 4 |
0,27 |
0,74 |
|
MgC0 3 |
0,0001 |
0,001 |
|
BaC0 3 |
0,00007 |
0,00006 |
|
BaS0 4 |
0,000002 |
|
|
Temperature, °C |
Air |
H 2 CO 3 |
CO 2 |
H 2 S |
NH3 |
|||
|
0,20 |
0,019 |
0,041 |
1,20 |
4,37 |
1,049 |
|||
|
0,16 |
0,019 |
0,032 |
1,18 |
3,59 |
0,812 |
|||
|
0,14 |
0,019 |
0,028 |
0,90 |
2,90 |
0,654 |
The air dissolved in water is richer in oxygen than atmospheric air. It contains 33.7% oxygen and 66% nitrogen.
1. The most common elements in living organisms are:
A) C, O, S, N; b) H, C, O, N; c) O, P, S, C; d) N, P, S, O.
2. The biological significance of the main macronutrients in the composition of living organisms is mainly due to their:
A) valence; b) the ability to form stronger chemical bonds than other elements; c) prevalence in the earth's crust;
d) valency and the ability to form stronger chemical bonds than other elements.
3. Carbon as an element is part of:
A) proteins and carbohydrates b) carbohydrates and lipids
C) carbohydrates and nucleic acids d) all organic compounds of the cell
4. Nitrogen as an element is part of:
A) proteins; b) proteins and nucleic acids
C) nucleic acids, proteins and ATP d) proteins, nucleic acids and lipids
5. Hydrogen as an element is part of:
A) water, mineral salts and carbohydrates; b) water, carbohydrates, proteins and nucleic acids
6. Oxygen as an element is part of:
A) water, mineral salts and carbohydrates b) water, carbohydrates, proteins and nucleic acids
C) water, carbohydrates, lipids and nucleic acids d) all inorganic and organic compounds of the cell
7. Phosphorus as an element is part of:
A) nucleic acids b) nucleic acids and ATP
C) nucleic acids and ATP, some mineral salts and lipids
D) nucleic acids, ATP, some mineral salts and proteins
8. Sulfur as an element is part of:
A) some proteins b) some mineral salts
C) some proteins and mineral salts d) some proteins and lipids
9. Hydrophilic compounds mainly include:
A) mineral salts b) mineral salts and some carbohydrates
C) some carbohydrates and amino acids d) mineral salts, some carbohydrates and amino acids
10. Hydrophobic compounds mainly include:
A) lipids b) mineral salts and lipids c) lipids and amino acids
d) mineral salts and amino acids
11. Water has the ability to dissolve substances because its molecules:
A) they are polar b) they are small in size c) they contain atoms connected by an ionic bond d) they form hydrogen bonds with each other
12. Potassium and sodium ions enter through the cell membrane through:
13. The concentration of potassium and sodium ions in the cell:
A) the same on its outer and inner surfaces
B) different, there are more sodium ions inside the cell, potassium ions - outside.
C) different, there are more potassium ions inside the cell, sodium ions - outside.
D) in some cases the same, in others different.
14. Regular structure biopolymers include:
A) polysaccharides b) polysaccharides and proteins
C) polysaccharides and nucleic acids d) nucleic acids and proteins
15. Biopolymers of irregular structure include:
A) proteins b) nucleic acids c) nucleic acids and proteins
d) nucleic acids and polysaccharides
16. Monosaccharides include:
A) glucose, ribose, fructose b) galactose, maltose, sucrose
C) fructose, lactose, sucrose d) maltose, ribose, sucrose
17. Disaccharides include:
A) ribulose, galactose, fructose b) ribose, mannose, maltose
C) maltose, lactose, sucrose d) sucrose, fructose, ribulose
18. Polysaccharides include:
A) starch, ribulose, mannose b) glycogen, glucose, cellulose
C) cellulose, starch, glycogen d) starch, cellulose, mannose
19. A sucrose molecule consists of residues:
A) glucose b) glucose and fructose c) fructose and glucose d) glucose and galactose
20. A starch molecule consists of residues:
A) glucose b) fructose c) fructose and glucose d) glucose and galactose
21. A glycogen molecule consists of residues:
A) glucose b) galactose c) glucose and galactose d) galactose and fructose
22. Triglycerides (esters of glycerol and higher fatty acids) are:
A) fats b) oils c) oils and fats d) fats, oils and phospholipids
23. Phospholipid molecule has:
A) hydrophilic head and hydrophobic tail b) hydrophobic head and hydrophilic tail c) hydrophilic head and tail d) hydrophobic head and tail
24. In aqueous solutions, amino acids exhibit the following properties:
a) acids b) bases
c) acids and bases d) in some cases acids, in others - bases
25. The primary structure of a protein is determined by amino acid residues:
a) number b) sequence c) number and sequence d) types
26. The primary structure of a protein is supported by bonds:
a) peptide b) hydrogen; c) disulfide;
d) hydrophobic.
27. The secondary structure of a protein is determined by:
a) spiralization of the polypeptide chain;
b) the spatial configuration of the polypeptide chain;
c) the number and sequence of amino acids of the spiralized chain;
d) the spatial configuration of the spiralized chain.
28. The secondary structure of a protein is mainly supported by bonds:
a) peptide b) hydrogen c) disulfide d) hydrophobic
29. The tertiary structure of a protein is determined by:
a) spiralization of the polypeptide chain
b) the spatial configuration of the spiralized polypeptide chain
c) the connection of several polypeptide chains
d) spiralization of several polypeptide chains
30. The tertiary structure of a protein is mainly supported by bonds:
a) ionic b) hydrogen c) disulfide d) hydrophobic
31. The quaternary structure of a protein is determined by:
a) spiralization of the polypeptide chain
b) the spatial configuration of the polypeptide chain
c) spiralization of several polypeptide chains
d) the connection of several polypeptide chains.
32. In maintaining the quaternary structure of the protein, the following are not accepted:
a) peptide b) hydrogen c) ionic d) hydrophobic.
33. The physicochemical and biological properties of a protein are completely determined by the structure:
a) primary b) secondary c) tertiary d) quaternary.
34. Fibrillar proteins include:
c) myosin, insulin, trypsin d) albumin, myosin, fibroin.
35. Globular proteins include:
a) fibrinogen, insulin, trypsin b) trypsin, actin, elastin
c) elastin, thrombin, albumin d) albumin, globulin, glucagon.
36. A protein molecule acquires natural (native) properties as a result of structure self-assembly
a) primary b) mostly primary, rarely secondary
c) Quaternary d) mostly tertiary, rarely Quaternary.
37. Monomers of nucleic acid molecules are:
a) nucleosides b) nucleotides c) polynucleotides d) nitrogenous bases.
38. DNA molecule contains nitrogenous bases:
a) adenine, guanine, uracil, cytosine b) cytosine, guanine, adenine, thymine
c) thymine, uracil, thymine, cytosine d) adenine, uracil, thymine, cytosine
39. An RNA molecule contains nitrogenous bases:
a) adenine, guanine, uracil, cytosine b) cytosine, guanine, adenine, thymine c) thymine, uracil, adenine, guanine d) adenine, uracil, thymine, cytosine.
40. The composition of the monomers of DNA and RNA molecules differs from each other in the content of:
a) sugar b) nitrogenous bases c) sugar and nitrogenous bases d) sugar, nitrogenous bases and phosphoric acid residues.
41. Purine nitrogenous bases that make up DNA include:
a) adenine and thymine b) uracil and cytosine c) adenine and guanine d) cytosine and thymine
42 The pyrimidine nitrogenous bases that make up DNA include:
a) adenine and thymine b) uracil and cytosine c) adenine and guanine d) cytosine and thymine.
43. Purine nitrogenous bases that are part of RNA include: a) adenine and uracil b) adenine and guanine c) cytosine and thymine d) cytosine and uracil
44 To pyrimidines. The nitrogenous bases that make up RNA are:
a) adenine and uracil b) adenine and guanine c) cytosine and thymine d) cytosine and uracil
45. In the composition of DNA, the ratio of nucleotides is constant
a) A+G/T+C b) A+T/G+C c) A+C/T+G d) A/G, T/C.
46. In the composition of RNA, the ratio of nucleotides is constant:
a) A+G/T+C b) A+G/U+C c) A+U/G+C d) A/G, U/C.
47. During the synthesis of DNA and RNA molecules, a polynucleotide chain is formed due to links between: a) sugar residues of nucleotides b) residues of phosphoric acids and sugars of nucleotides
c) nitrogenous bases and sugar residues of nucleotides d) nitrogenous bases and phosphoric acid residues of nucleotides.
48. The secondary structure of DNA is supported by links between:
a) neighboring nucleotides of one of the chains
b) phosphoric acid residues of nucleotides in two chains
d) non-complementary nitrogenous bases of nucleotides in two chains.
49. The connection of two polynucleotide chains into a DNA helix is carried out by bonds:
a) ionic b) hydrogen c) hydrophobic d) electrostatic.
50. The number of bonds that arise in the complementary base pair of adenine-thymine of the DNA molecule is: a) 1 b) 2 c) 3 d) 4.
51. The number of bonds that occur in a complementary base pair of guanine-cytosine of a DNA molecule is: a) 1 b) 2 c) 3 d) 4.
52. The number of variants of complementary base pairs of DNA nucleotides is:
a) 2 b) 3 c) 4 d) 5.
53. The distance between the sugar-phosphate backbones of two DNA strands is equal to the distance occupied by:
a) a pair of purine bases b) a pair of pyrimidine bases
c) one purine and one pyrimidine base; d) two purine and two pyrimidine bases.
54. A full turn of the DNA double helix falls on:
a) 5 base pairs b) 10 base pairs c) 15 base pairs d) 20 base pairs
55. The model of the structure of the DNA molecule was proposed by J. Watson and F. Crick in:
a) 1930 b) 1950 c) 1953 d) 1962
56. A cell contains DNA in:
a) nucleus b) nucleus and cytoplasm c) nucleus, cytoplasm and mitochondria d) nucleus, mitochondria and chloroplasts.
57. The largest molecular sizes are:
a) tRNA b) snRNA c) mRNA d) rRNA.
58. Protein biosynthesis in a cell mainly involves:
a) DNA. mRNA b) mRNA, tRNA c) tRNA, rRNA d) mRNA, rRNA
59. ATP molecule contains:
a) adenine, deoxyribose and three phosphoric acid residues b) adenine, ribose and three phosphoric acid residues c) adenosine, ribose and three phosphoric acid residues d) adenosine, deoxyribose and three phosphoric acid residues.
60. In an ATP molecule, phosphoric acid residues are interconnected by bonds:
a) two hydrogen b) two electrostatic c) two macroergic ..
d) three macroergic.
Topic: Chemical composition of the cell.
Complete the sentences by filling in the necessary terms and concepts instead of dots.
1. A water molecule that carries a positive charge at one end and a negative charge at the other is called ....
2. Substances that are highly soluble in water are called ....
3. Substances that are poorly soluble and completely insoluble in water are called ....
4. The difference between the concentrations of K + and Na + ions inside and outside the cell creates on its membrane ....
5. Carbohydrates ribose, glucose. Sucrose chemically belongs to ....
6. Carbohydrates maltose, lactose, sucrose by chemical structure belong to ...
7. Carbohydrate starch. glycogen, cellulose in chemical structure belong to ....
8. Molecules of any polymer consist of many repeating units -…
9. The sucrose molecule consists of glucose residues and - ...
10. The monomer of starch, glycogen and cellulose molecules is ...
11. The main biological function of monosaccharides in the cell is ...
12. The product of the esterification reaction between glycerol and higher fatty acids - ...
13. Higher fatty acids (oleic, linolenic) containing double bonds are called ...
14. Higher fatty acids (palmitic, stearic), in the molecule of which there are no double bonds, are called ...
15. Triglycerides containing residues of glycerol and solid fatty acids are called ...
16. Triglycerides containing residues of glycerol and liquid fatty acids are called ...
17. The main biological function of phospholipids in the cell is ...
18. The monomers of protein molecules are...
19. Part of an amino acid molecule that determines its unique properties ...
20. Amino acids that are not synthesized in the animal body and are obtained only in finished form with food are called ...
21. A compound formed as a result of a condensation reaction of two amino acids ...
22. The number and sequence of amino acid residues in the polypeptide chain - ...
23. Neighboring amino acid residues in the polypeptide chain are connected to each other using ...
24. Amino acid residues in adjacent turns of the helix of the polypeptide chain are connected together using ...
25. The first protein for which it was possible to find out its amino acid sequence was ...
26. A special geometric shape characteristic of each protein is called ...
27. The process of loss of its natural structure by a protein molecule under the influence of various factors is called ...
28. The process of spontaneous restoration of the natural structure of a denatured protein is called ...
29. The monomers of DNA and RNA molecules are ...
30. The five-carbon sugar that is part of the DNA molecule is ...
31. Nitrogenous bases: adenine and guanine, which are part of nucleic acid molecules, belong to the class ...
32. Nitrogenous bases: cytosine, thymine, uracil, which are part of nucleic acid molecules, belong to the class ...
33. Compound of a five-carbon sugar with a nitrogenous base - ...
34. A compound formed as a result of a condensation reaction of two nucleotides - ...
35. Two antiparallel DNA chains are connected to each other through nitrogenous bases according to the principle ...
36. The secondary structure of DNA is maintained mainly with the help of ...
37. In the cell nucleus, DNA is part of ...
38. The process of self-reproduction of DNA molecules, providing accurate copying of genetic information ...
39. One of the DNA chains has the nucleotide sequence AATTGCCGGA. The second chain complementary to it will have a nucleotide sequence ...
40. Adenyl nucleotide connected to two phosphoric acid residues - ...
