Which of these are chemical compounds?
\(O \ _{2} \)
\(H _{2}O \)
\(CO _{2} \)
\(N _{2} \)
Which of these are chemical compounds?
\(O \ _{2} \)
\(H _{2}O \)
\(CO _{2} \)
\(N _{2} \)
