If 4 g of NaOH dissolves in 36 g of H2O, the molarity of the solution is: (specific gravity of solution is 1 g mL-1) :
1. | 3 M | 2. | 3.5 M |
3. | 2.5 M | 4. | 2 M |
On complete decomposition, the volume of CO2 released at STP on heating 9.85 g of BaCO3 (atomic mass, Ba = 137) will be:
1. 1.12 L
2. 4.84 L
3. 2.12 L
4. 2.06 L
The amount of Zinc (atomic weight = 65) necessary to produce 224 mL of H2 (at STP) by the reaction with dilute sulphuric acid will be:
1. | 0.65 g | 2. | 7.6 g |
3. | 6.5 g | 4. | 8.5 g |
The number of valence electrons present in 0.53 grams of Na2CO3 is:
1.
2.
3.
4.
The number of moles present in 2.5 litres of 0.2 M are:
1. 0.25
2. 0.5
3. 0.75
4. 0.2
The maximum number of molecules is present in which of the following?
1. 15 L of gas at STP
2. 5 L of gas at STP
3. 0.5 g of gas
4. 10 g of gas
Two students performed the same experiment separately, and each of them recorded two readings of mass, which are given below. The correct reading of mass is 3.0 g. On the basis of the given data, mark the correct option out of the following statements.
Students | Readings | |
(i) | (ii) | |
A | 3.01 | 2.99 |
B | 3.05 | 2.95 |
1. | The results of both the students' are neither accurate nor precise. |
2. | The results of student A are both precise and accurate. |
3. | Student B's results are neither precise nor accurate. |
4. | The results of student B are both precise and accurate. |
1. 1.5 M
2. 1.66 M
3. 0.017 M
4. 1.59 M
2. 46 g Na
3. 0.40 g Ca
4. 12 g He
The empirical formula and molecular mass of a compound are and 180 g, respectively. The molecular formula of the compound is:
1. C9H18O9
2. CH2O
3. C6H12O6
4. C2H4O2