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Anonymous users2024-02-11CaCO3+H2SO4=CASO4+H2O+CO2 Ca(OH)2+2HNO3=Ca(NO3)2+2H2O can react with acidic oxides, which can change the color of the indicator, etc.
Add sodium carbonate solution, there are bubbles to produce dilute hydrochloric acid, and white precipitate to produce lime water.
40g*hcl + naoh=nacl+h2o
x*20%x=80g
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Anonymous users2024-02-10Blowing with a straw and mouth is very simple, and the turbidity is lime water.
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Anonymous users2024-02-092hno3+ca(oh)2=ca(no3)2+2h2o2.can react with acids.
3.When CO2 is introduced, the same is dilute hydrochloric acid, and the turbidity is lime water. Gram.
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Anonymous users2024-02-08Acid rain containing sulfuric acid corrodes the chemical equation of marble caCO3 + H2SO4 = CaSO4 + H2O + CO2
The equation for the reaction of acid rain containing nitric acid with hydrated lime is Ca(OH)2+2HNO3=Ca(NO3)2+2H2O
Please write one more article: can react with acids or are both bases.
Identification: Dropwise added to the sulfuric acid solution, if there is a white precipitate generated, it is lime water, and if there is no phenomenon, it is dilute hydrochloric acid.
The solute mass fraction is how much HCl is contained in 40g of HCL in g: 40*.
How many g:g of a caustic soda solution with a solute mass fraction of 20% is needed to react exactly completely with this hydrochloric acid with enough caustic soda solution
HCl+NaOH = NaCl+H2O, they are a 1:1 reaction. Suppose caustic soda x g is required, its molecular weight is 40, and the molecular weight of hydrochloric acid is 36,, therefore, 20%*x40=, x=80
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Anonymous users2024-02-07It proves that the purple litmus turns red when it is acid.
Prove whether the water reacts with litmus and turns red.
Prove whether carbon dioxide reacts with litmus and turns red.
Prove whether it is carbon dioxide and water that make litmus red.
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Anonymous users2024-02-061.Prove that the litmus test strips are normal and usable.
2.Prove that the water is not acidic.
3.Proof that CO2 is not acidic.
4.It is proved that H2CO3 is produced, indicating that H2O reacts with CO2.
1) The experiments done by the students have no reference and cannot explain anything, and they only see a phenomenon, and the specific cause still needs to be analyzed.
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Anonymous users2024-02-05Proof that acidic substances can turn litmus red Proof of water Dried carbon dioxide cannot turn litmus red Proof that water reacts with carbon dioxide to form acidic substances.
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Anonymous users2024-02-04Solution: The molecular weight of iron oxide is 160 There are two irons in an iron oxide molecule The atomic weight of iron is 56
So Fe2O3 has Fe 56*2 160
Then there is iron in the hematite (56*2 160)*80%=56%.
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Anonymous users2024-02-032h2so4+caco3=ca(so4)2+h2o+co2
2hno3+ca（oh）2=ca(no3)2+2h2o
All are alkaline. All are absorbent.
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Anonymous users2024-02-02cuso4 + fe = feso4 + cu56---64
56g---x
x = 64g The mass of copper produced by the reaction is 64g
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Anonymous users2024-02-0156 grams of iron is 1mol of iron, and if it is added to cuso4, it will produce 2-valent iron, then it will be 64*2 2=64
cuso4 + fe = feso4 + cu56---64
56g---x
x = 64g The mass of copper produced by the reaction is 64g
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Anonymous users2024-01-31Hello, first write the chemical equation.
fe+cuso4=cu+feso4
56 160 64 152 Relative molecular mass 56g 64g reactant mass.
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Anonymous users2024-01-30The energy produced by the oxidation of fats and oils is (1) times more than that produced by the oxidation of sugars, and oils and fats are divided into (vegetable) oils and (animal) fats.
It is usually solid at room temperature (animal fat - fat), and liquid at room temperature (vegetable oil - oil).
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Anonymous users2024-01-291 Solid liquid state.
Animal fats and fats Vegetable fats and fats.
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Anonymous users2024-01-281) Mass ratio of iodine, potassium and oxygen in potassium iodate = 127:39:16x3 = 127:39:48
2) Mass fraction of iodine in potassium iodate = 127 (127 + 39 + 16x3) x 100% =
3) the mass of iodine to be reduced per kilogram of salt = 40mg-25mg=15mg; Each sachet (500g) should reduce iodine by 15mg2=
Less potassium iodate mass = =
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Anonymous users2024-01-271. The mass ratio is 127:39:16*3=127:39:48
2. Mass fraction = 127 (127 + 39 + 48) =
5*(40-25)=, that is, less per band.
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Anonymous users2024-01-261) According to the inscription, it can be known that the solution with a mass fraction of 10% to 117g is NaCl solution, then the mass of solute sodium chloride m (NaCl) =
Equation: 2NaOH + MgCl2 ==2NaCl + Mg(OH)2 precipitation.
95g 117gmm=
Mass disturbance of magnesium chloride w=(
2) 2NaOH + MgCl2 ==2NaCl + Mg(Oh)2 precipitate.
80g 117g
MM = 8g of sodium hydroxide solute mass fraction w = (8g 117g) * 100% =
1g of pure calcium carbonate emits carbon dioxide.
Indicates that the impurities are comparable to calcium carbonate. >>>More
Grasp the key points, the focus is on the acid and alkali salt part, the experiment of gas, and the calculation of the solute mass fraction in the solution, and the other parts pay attention to the mastery of basic knowledge.
You enter it in the library.
Summary of the third chemistry solution acid-base salts. >>>More
First of all, answer the first question, molecules, atoms, ions, which are all microscopic ways to understand the form of matter. To be precise, the atom can be considered to be the most basic unit of various elements in nature, which is composed of the nucleus and the outer orbital electrons (also known as bound electrons or circumferential electrons); A molecule is made up of atoms, which can be made up of atoms of the same kind, as you call the elemental metal (k, na, fe......Oxygen (O2), diamond (C), and molecules can also be composed of multiple atoms, such as carbon dioxide (CO2) and water (H2O), which are the smallest particles that exist independently and maintain the chemical properties of matter; Ions, on the other hand, are obtained by molecules (i.e., electrolytes) that can be ionized under certain conditions (e.g., dissolved in certain solvents, heated and melted, etc.), such as hydrogen ions H+, acid ions (sulfate SO42-, carbonate CO32-......).Wait a minute. >>>More
Hello this classmate! I am a chemistry teacher and have been teaching chemistry for six years, and it is common for most students to have a situation like yours. In fact, it is not difficult to study hard, as a new subject, most students will have this situation with you. >>>More