Which substances exhibit only london forces ? ? he, h2o, hcl, cl2

He and Cl2

Explanation:

London forces are displayed by substances that are nonpolar such as gas molecules and nonpolar covalent bonds. H2O and HCl all contain polar covalent bonds. Hydrogen is bonded to a highly electronegative atom hence these substances exhibit hydrogen bond.Cl2 is nonpolar, same applies to He. Cl2 is a formed by a homonuclear covalent bond hence both He and Cl2 contain only London forces.

i can ! i just need to know what the paragraph is! : p

- 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