What is the relative formula mass of N2O?
Ar of N = 14 and Ar of O = 16.
30
44
46
What is the relative formula mass of Ca(NO3)2?
Ar of Ca = 40, Ar of N = 14 and Ar of O = 16.
70
102
164
What does the law of conservation of mass state?
No atoms are lost or made in a chemical reaction
Atoms are lost but not made in a chemical reaction
Atoms are made but not lost in a chemical reaction
Which of these is an example of a non-enclosed system?
A boiling tube in which two solutions react to form a solution and a precipitate
A test tube in which calcium carbonate is heated
A beaker in which an acid neutralises an alkali to form a salt solution
2.0 g of copper sulfate is dissolved in 0.5 dm3 of solution. What is the concentration of the solution?
4.0 g/dm3
0.25 g/dm3
1.0 g/dm3
A solution of potassium chloride has a concentration of 20 g/dm3. What mass of potassium chloride is dissolved in 5 dm3 of the solution?
4 g
100 g
0.25 g
What is the relative formula mass of Al2(SO4)3? - HIGHER
Ar of Al = 27, Ar of S = 32 and Ar of O = 16
342
150
75
What is the number of molecules in 23 g of NO2? - HIGHER
(Mr of NO2 = 46)
1.204 × 1024
6.02 × 1023
3.01 × 1023
What amount of O2 reacts with 4 mol of Al in the following reaction? - HIGHER
4Al + 3O2 → 2Al2O3
3 mol
2 mol
4 mol
What mass of Al reacts with 96 g of oxygen in the following reaction? - HIGHER
Mr of O2 = 32 and Ar of Al = 27.
54 g
108 g
27 g