Practice Writing Chemical Formulae (3.4) - Atoms and Molecules

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9 questions

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6 sample questions

Question 1.
Write the formula for sodium chloride.
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Consider the charges of sodium and chloride ions.
Question 2.
What is the formula for water?
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Count the number of hydrogen and oxygen atoms.
3Question 3.
What is the formula for magnesium chloride?
- MgCl
- MgCl₂
- Mg₂Cl
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Pay attention to the charges!
4Question 4.
True or False: The formula for sodium sulfate is NaSO₄.
- True
- False
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Think of the charge balance!
Question 5.
A compound consists of sodium and sulfate ions. If sodium has a valency of +1 and sulfate has a -2 charge, how do you write the correct formula?
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Think about how many sodium ions you need to balance the charge.
Question 6.
If a compound contains magnesium and phosphate, where magnesium has a +2 valency and phosphate has a -3 charge, what is the formula?
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Use the criss-cross method to balance the charges.

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