Chemistry calculation question in the third year of junior high school A student is determined wheth

CaCO3 + 2HCl = CACl2 + H20 + C02 is the initial substance, calcium tablets + hydrochloric acid, and the remaining substances are: calcium tablets + hydrochloric acid after carbon dioxide is released.

Hence the mass of carbon dioxide is.

According to the mass of carbon dioxide, it can be calculated that the mass of calcium carbonate contained in 4 calcium tablets is 100*, then the mass of calcium carbonate in each tablet: 5 4=

If you can understand the process, you can calculate it yourself hehe.

According to the law of conservation of mass, m (carbon dioxide) = m (before the reaction) - m (after the reaction) = m (calcium tablets) + m (hydrochloric acid) - m (remaining) = 4*

caco3+2hcl=cacl2+h20+c02m(caco3)

100 44= m(caco3) The solution is m(caco3)=5g, then the calcium carbonate in each calcium tablet is 5g 4= > So the label is true.

caco3+2hcl=cacl2+co2+h2o

x, x = 10 grams, the mass fraction of calcium carbonate is 10 (10+

Calcium carbonate contains 40% calcium, 10 grams, calcium carbonate mass = grams.

1.Second, the quality of carbon oxide in Lushan was examined. 4*

caco3+2hcl=cacl2+h2o+co2x y

100/x=73/y=44/

x=5g y=

2.The mass fraction of the solute in the dilute hydrochloric acid is scarce. Defeat 40g*100%=3Determine whether the content of calcium carbonate in calcium tablets is true by calculation.

5g 4=> true.

solution, let the mass of caco3 involved in the reaction be x

caco3+2hcl=cacl2+co2+h2ox 11．1g

x 10 g The mass fraction of calcium carbonate in this calcium supplement is 10 (10 2 5) 100 80

Mass fraction of calcium in calcium carbonate 40 (40 12 16 3) 100 40

The mass of calcium in this calcium supplement is 10g 40 4g

This calcium supplement is taken daily.

Hope that helps.

CaCO3+2HCl=CaCl2+H2O+CO2X=15G1) Is the mass of calcium carbonate in each tablet more than the remainder?

15 Sell 10=

2) What is the mass of elemental calcium per tablet?

3) By calculating, hail rolling, what conclusion do you draw?

It is a qualified product.

Enthusiastic netizens are me, I just signed up for one.

(1) If this product is pure calcium carbonate, the relative molecular weight of calcium carbonate is 100, and the mass fraction of calcium is 40

100 100% = 40%, and the calcium content of each tablet is: 40g50 40% =

Therefore, it is impossible for each tablet of this product to contain calcium, and the calcium content in this label is wrong (2) The mass of carbon dioxide gas generated is: 22g+, and the mass of calcium carbonate in 10 calcium tablets is X, CaCO3+2HCl=CaCl2+H2O+CO2 100 44X

x=, so the mass of calcium carbonate contained in each of these calcium tablets is.

10= The calcium content of each tablet is;

Answer: (1) The calcium content in this label is wrong by calculating (2) The quality of calcium carbonate in each calcium tablet is; The calcium content is calcium per tablet.

Sodium hydroxide + carbon dioxide reacts to produce sodium carbonate, so the CO2 of the reaction can be determined, and then the mass of calcium carbonate should be calculated according to the mass of carbon dioxide, and the mass fraction of calcium = 40 100 * 5 25g = 8%.

,caco3%=5/25*100%=20%

ca%=40/100*5/25g=8%

2.[Tag]: XX brand lightweight: caCO3 Content: 8% calcium quality 25g XX chemical factory products.