Question

1) why is the reaction between Sodium sulphate and Barium Chloride are called chemical double displacement reaction?
2) name two metals which can displace hydrogen from hcl?
how can you test co2 gas evolved when sodium carbonate react with Hcl?
3) when ferous sulphate crystals are heated one of the precuation is to keep the mouth of test tube slanting down ward during initail heating why ?
please answer to this questions it is urgent

Answer 1

1) because there is the exchange of ions take place.when sodium sulphate react with barium chloride to form sodium chloride and barium sulphate.they exchange there ions.which is known as double displacement reaction.

2) Sodium (Na) & Calcium(Ca) can displace the hydrogen from HCl.

=>By passing the gas evolved in the reaction of sodium carbonate and HCl to the lime water.
As CO2 turns lime water milky.

Answer 2

1)- In this reaction the exchange of ions takes place betwwen both the reagents with each other....so...it is called the double displacement reaction...