Question

Chemical weathering over hundreds of thousands of years formed modern caves. One form of chemical weathering occurs when carbon dioxide reacts with water to produce carbonic acid, H2CO3
. How many bonds formed in H2CO3
? Each of the elements found in carbonic acid has the number of valence electrons shown:

H
valence electrons: 1
C
valence electrons: 4
O
valence electrons: 6
Based on this information, how many single and how many double bonds are found in carbonic acid?

(1 point)
Responses

4 single bonds and 0 double bonds
4 single bonds and 0 double bonds

6 single bonds and 1 double bond
6 single bonds and 1 double bond

4 single bonds and 1 double bond
4 single bonds and 1 double bond

6 single bonds and 0 double bonds

Answer 1

Answer: 4 single bonds and 1 double bond.

Reason: The structure is H–O–C(=O)–O–H. There are two O–H single bonds and two C–O single bonds (4 singles total) plus one C=O double bond.