Laws of Mass Conservation

Q.

What is the equivalent weight of Calcium carbonate ${\mathrm{CaCO}}_3$?

Q. If the law of conservation of mass was to hold true, then $20.8\text{g}$ of $BaC{l}_2$ on reaction with $9.8\text{g}$ of $H_{2}S{O}_4$ will produce $7.3\text{gm}$ of $HCl$ and what mass of $BaS{O}_4$?

1. $11.65\text{g}$
2. $23.3\text{g}$
3. $25.5\text{g}$
4. $30.6\text{g}$

Q. Phosphoric acid is prepared in a two-step process. Find the mass of $H_{3}P{O}_4$ formed when 124 g of $P_4$ reacts with an excess of oxygen and then treated with sufficient water.
$P_4+O_2⟶P_4{O}_{10}$
$P_4{O}_{10}+H_{2}O⟶H_{3}P{O}_4$
(Molar mass of P = 31 g/mol)

1. 150 g
2. 288 g
3. 560 g
4. 392 g

Q. An unbalanced chemical reaction is a violation of the law of:

1. Conservation of mass
2. Constant proportions
3. Reciprocal proportions
4. Multiple proportions

Q.

$10.0\mathrm{g}$ of Calcium carbonate on heating gave $4.4\mathrm{g}$ of Calcium oxide and $5.6\mathrm{g}$ of Carbon dioxide. Show that these observations are in agreement with law of conservation of mass.

Q.

Rate of reaction is proportional to product of molar concentration of reactants with each concentration term raised to power its stiochiometric coefficient. This is the law of

1. Mass action

2. Equilibrium

3. Constant proportion

4. Reciprocal proportions

Q.

According to the law of conservation of mass, the mass of the products is equal to the mass of the reactants.

1. True
2. False

Q. Which of the following is the best example of the law of conservation of mass?

1. 12 g of carbon combines with 32 g of oxygen to form 44 g of carbon dioxide.
2. When 12 g of carbon is heated in a vacuum, there is no change
   in mass.
3. A sample of air increases in volume when heated at constant pressure but its mass remains unaltered.
4. The weight of a piece of platinum is the same before and after heating in air.

Q. In terms of Charles' law, explain why - 273 ${}^{\circ }C$ is the lowest possible temperature.

Q. A mixture of pure $AgCl$ and $AgBr$ is found to contain a total of 60.94% $Ag$ by mass. What is the mass % of chlorine in the mixture?
(Molar mass of Ag = 108 g/mol, Cl = 35.5 g/mol, Br = 80 g/mol)

1. 4.85%
2. 9.64%
3. 8.45%
4. 7.23%

Q. If $21\text{g}$ of $NaHC{O}_3$ is added to $15\text{g}$ of $C{H}_{3}COOH$ solution, the residue is found to weigh $25\text{g}$. what is the mass of $C{O}_2$ is released in the reaction?

1. $11\text{g}$
2. $12\text{g}$
3. $13\text{g}$
4. $10\text{g}$

Q. Avogadro number NA is changed fromx 1023 mol-1 to 6.022 x 1020 mol-1, this5 If\lbrack Re-AIPMT-2015\rbrack would changeThe ratio of chemical species to each other ina balanced equation13(2) The ratio of elements to each other in acompound(3) The definition of mass in units of grams(4) The mass of one mole of carbon

Q. Which of the following is the best example of law of conservation of mass?

1. $12g$ of carbon combines with $32g$ of oxygen to form $44g\text{of}C{O}_2$
2. When $12g$ of carbon is heated in a vacuum there is no change in mass.
3. The weight of a piece of platinum is the same before and after heating in air.
4. A sample of air increases in volume when heated at constant pressure but its mass remains unaltered

Q. 10.0 g of $CaC{O}_3$ on heating gave 4.4 g of $C{O}_2$ and x g of $CaO$. Applying the law of conservation of mass, calculate the mass of $CaO$.

1. 6.5 g
2. 5.6 g
3. 4.2 g
4. 5.3 g

Q. When 0.0976 g of magnesium was heated in air, 0.1627 g of magnesium oxide $\left(MgO\right)$ was produced. What is the mass of oxygen needed to produce 0.1627 g of $MgO$?

1. $0.0651\text{g}$
2. $0.0782\text{g}$
3. $0.0440\text{g}$
4. $0.0200\text{g}$

Q. $S\left(s\right)+O_2\left(g\right)\to S{O}_2\left(g\right)$
$S{O}_2\left(g\right)+C{l}_2\left(g\right)+2H_{2}O\to H_{2}S{O}_4\left(l\right)+2HCl\left(l\right)$
$H_{2}S{O}_4\left(l\right)+BaC{l}_2\to BaS{O}_4\downarrow +2HCl$

112 g of sulphur is burned initially to form $S{O}_2$. Find the amount of $BaS{O}_4$ precipitate obtained in the series of reactions.
(Molar mass of Ba = 137 g/mol)

1. 815.5 g
2. 456.3 g
3. 635.7 g
4. 988.1 g

Q. Calculate the mass of hydrated copper sulphate required to produce 56.90 g of the complex compound assuming other reagents to be present in excess.
$CuS{O}_4.5H_{2}O\to CuS{O}_4+5H_{2}O$
$CuS{O}_4+2KCN\to Cu(CN{)}_2+K_{2}S{O}_4$
$2Cu(CN{)}_2\to 2CuCN+(CN{)}_2$
$2CuCN+6KCN\to 2K_3\left[Cu\right(CN{)}_4]$

$(\text{Molar mass of}K=39g/mol,Cu=63.5g/mol)$

1. 122.4 g
2. 19.96 g
3. 12.24 g
4. 49.9 g

Q. An unbalanced chemical reaction is a violation of the law of:

1. Conservation of mass
2. Constant proportions
3. Reciprocal proportions
4. Multiple proportions

Q. 24 g of $K_{2}C{O}_3$ was treated by a series of reagents to convert all of the carbon to cyanide ions in the complex $K_{3}Z{n}_3\left[Fe\right(CN{)}_6{]}_2$. Calculate the weight of the complex formed.
(Molar mass of K = 39 g/mol, Fe = 56 g/mol, Zn = 65 g/mol)

1. 15.85 g
2. ​​​​​10.67 g
3. 6.35 g
4. 20.74 g

Q. Laws ofchemical combination can be explain on the basis of a.Gay Lussac Law b.Dalton atomic theory explai

Q. $S\left(s\right)+O_2\left(g\right)\to S{O}_2\left(g\right)$
$S{O}_2\left(g\right)+C{l}_2\left(g\right)+2H_{2}O\to H_{2}S{O}_4\left(l\right)+2HCl\left(l\right)$
$H_{2}S{O}_4\left(l\right)+BaC{l}_2\to BaS{O}_4\downarrow +2HCl$

112 g of sulphur is burned initially to form $S{O}_2$. Find the amount of $BaS{O}_4$ precipitate obtained in the series of reactions.
(Molar mass of Ba = 137 g/mol)

1. 815.5 g
2. 456.3 g
3. 635.7 g
4. 988.1 g

Q.

Five grams of $KCl{O}_3$ yield 3.041 g of $KCl$ and 1.36 L of oxygen at standard temperature and pressure. Do these figures support the law of conservation of mass within limits of $\pm 0.4\%$ error?

1. True

2. False

Q. Write an equation to calculate Rf value of compound

Q. Discuss the principle of estimation of halogens, sulphur and phosphorus present in an organic compound.