Science

metal + acid gives salt + hydgrogen

for example:-

zinc + hydrocholoric acid  - gives -zinc chloride + hydrogen

or,

zinc + suphuric acid - gives - zinc sulphate + hydrogen

matal carbonate + acid - gives - salt + carbondioxide + water

for example:

Magnesium carbonate + hydrochloric acid- gives- magnesium chloride + carbondioxide + water

OR,

Calcium carbonate + nitric acid - gives - calcium nitrate + carbondioxide + water

metal oxide + acid - gives - salt + water

for example:

copper oxide + sulphuric acid - gives - copper sulphate + water

metal + oxygen - gives - metal oxide,

for example,

iron + oxygen - gives - iron oxide,

and so on.