An 18-g sample of element A combines completely with a 4-g sample of element B to form the compound AB. What is the mass of the compound formed?

22g

Explanation:

Given parameters:

Mass of element A = 18g

Mass of element B  = 4g

Unknown:

Mass of compound formed = ?

Solution:

 The reaction equation is given as;

          A   +   B   →  AB

According to the law of conservation of mass "in a chemical reaction, matter is neither created nor destroyed but changed from one form to another".

Simply mas is conserved and the mass of the reactants is the same as the mass of the product that forms.

  Mass of reactants  = mass of A + mass of B = 18g + 4g  = 22g

 So;

  Mass of product AB = 22g

these nuts

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.