Select the correct word from the words in brackets to complete each sentence

Question

Select the correct word from the words in brackets to complete each sentence.

1. Melting point of organic compounds are ____ than that of inorganic compounds are ____. (high, lower) 
2. Organic compounds are ____ and inorganic compounds are ____ (covalent, electrovalent)
3. Kekule proposed C is ____ and vant Hoff proves C is ____  (tetra valent, tetrahedral)
4. Ethylene contains one ____ covalent bond and two ____ covalent bonds. (double, single)
5. The number of paired electrons in ethylene is  ____ and in acetylene is ____. (10, 12).