Which example shows a double replacement reaction?

KCl + AgNO₃ —> AgCl + KNO₃

Explanation:

To answer the question correctly, we must understand the definition of a double displacement reaction.

A double displacement reaction is a reaction in which the ions of the two reacting compounds exchange to form new compounds different from the two reacting compounds. Example is given below:

XY + AB —> XB + AY

Considering the options given in the question above, only the equation:

KCl + AgNO₃ —> AgCl + KNO₃

Satisfy the definition of a double displacement reaction.

120,630,890

step-by-step explanation:

110+10=120,620+10=630,880+10=890

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms