Question

Please help me answer this question

Answer 1

Answer with explanation:

1) general word equation=acid + metal= salt + hydrogen gas

chemical/balanced equation= 2HCl+Mg=MgCl2+H2

2)The gas thus formed is an effervescent carbon di oxide when calcium chloride reacts with hydrochloric acid. the carbon di oxide gas also acts as an extinguisher for fires. Hence the burning candle is extinguished.

Answer 2

1) metal reacts with acid to produce hydrogen gas and salt

an example of the reaction will be
2Na+ 2HCl —> 2NaCl +H2

2) we know the metal in compound A is calcium as one of the compound formed is calcium chloride.

the gas that’s causing effervescent effect is CO2 as CO2 is non polar and does not mix with water hence appears as bubbles. there are 2 possible calcium compounds that can produce CO2 with addition of HCl.

those compounds are calcium carbonate (CaCO3) and Calcium Bicarbonate ( Ca(HCO3)2 )

reaction for both possible compounds
- CaCO3 + 2HCl —> CaCl2 + H2O + CO2
- Ca(HCO3)2 + 2HCl —> CaCl2 + 2H2O +2CO2