Which substance is a binary compound? 1. barium 2. beryllium 3. carbon dioxide 4. calcium hydroxide?

The correct option is 3.

Explanation: Binary compounds are the compounds which are formed by the combination of 2 elements.

We are given some options, from that only 1 option is satisfying the definition of binary compounds, which is carbon dioxide

Carbon dioxide is made from the combination of two elements which are oxygen and carbon.

Option 1 and 2 are the elements.

Option 4: Calcium hydroxide is a compound made from the combination of more than 2 compounds which are calcium, hydrogen and oxygen. Hence, it cannot be considered as a binary compound.

Hence, the correct option is 3.

explanation:

detials on each model with digrams

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

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