Why do the reactants zinc and hcl(hydrochloric acid) indicate the reaction of single displacement?

 the reactant Zinc and HCl  indicate  the single  displacement  because

zinc  metal displaces  hydrogen from HCl to form   hydrogen  gas and  zinc chloride.

Explanation

A  single  displacement   reaction is type of reaction in which element  react  with  compound  and take the place of another  element  in that compound.

When Zn  react  with HCl ,  Zn (an element)  displaces H  from Hcl (compound) to  H₂ gas  and ZnCl₂ according to equation  below

Zn  +2 HCl→ znCl₂  +H₂

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"

points

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