Calculate the percentage by mass of nitrogen in calcium trioxonitrate(V).
[Ca = 40, N = 14, O = 16]
The droplets of water observed around a bottle of milk taken out of the refrigerator is due to the fact that the
saturated vapour pressure of the milk is equal to the atmospheric pressure
water vapour in the air around the bottle loses some of its energy to the bottle
water vapour in the air around the bottle gains some energy from the bottle
temperature of the milk drops as it loses heat into the surroundings
Calculate the volume of 0.5 mol dm-3 H2SO4 that is neutralized by 25cm3 of 0.1 mol dm-3 NaOH.
2Na(s) + 2HO(l) → 2NaOH(aq) + H2(g)
From the equation above, calculate the mass of sodium hydroxide produced by 2.3g of sodium .
[H = 1, O = 16, Na = 23]
The uncovered raw food that is sold along major roads is likely to contain some amount of
The colour of the fountain water is
Lead is used for making bullets and lead shots because of its
resistance to corrosion
low melting point
MnO2(s) + xHCl(aq) → MnCl2(aq) + yH2O(l) + zCl2(g)
In the equation above, what are the values of x, y and z respectively?
4, 1, 2
1, 2, 1
2, 1, 2
4, 2, 1
What is the volume of oxygen required to burn completely 45cm3 of methane at s.t.p?
Carbon exists naturally in the combined state as