3. The set up below was used to collect gas K, produced by the reaction between water and calcium metal. Gask Water calcium Metal (b) At the end of the experiment, the solution in the beaker was found to be a weak base. Explain why the solution is a weak base

Ca(s) + 2H2O(l) = Ca(OH) 2(aq) + 2H2(g)

The gas K collected is hydrogen gas.

The solution after the experiment is found to be weak base because Ca(OH)2 is sparingly soluble in water forming a weak base.

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.