Compounds

Which of these is a ball and stick model?

C

Which chemical formula is represented by the model?

CH4

Which statement describes compounds?

Compounds are represented by chemical formulas.

Susana heats up a sample of red crystals. While the sample is being heated, a gas is released and a blue powder is left after the heating. Is the sample of red crystals an element or a compound? Explain your answer.

Susana's red crystal sample is a compound because it was broken down into a gas and blue powder. It is not an element because elements cannot be broken down into simpler substances by ordinary means, such as heating.

Does this model represent a compound? Explain your answer.

The model does not represent a compound because it shows two atoms of the same element combined. To be a compound, the model would need to contain atoms of different elements, represented by different-colored balls.

What elements make up this compound? Check all that apply.

carbon hydrogen oxygen

Complete the sentence with the word "element" or "compound."

element compound

Which subscripts complete the chemical formula for the compound?

how many Cs and Hs

H is a chemical and H2 is a chemical

symbol formula

How many of each atom is present in this compound?

the numbers easy