9. The molar mass of Na2SO4 is 142.1 g/mol.

Calculate the number of moles in 10.0 g of Na2SO4.

• 7 x 6.02 x 10^23 x 142.1 g/mol

• 10.0 g / 142.1 g/mol

• 7 x 10.0g/142.1 g/mol

• 10.0g x 142.1 g/mol

A small block has a volume of 15 mL and a mass of 30g. What is its density?

What is a bond force that holds two atoms together

Why is it wrong to assume that you are only "doing science" while you are doing experiments?

A student has a 2.123 g sample of a hydrated salt. she heats it to drive off all the water. after heating to constant mass, the salt weighs 1.861 g. the anhydrous salt is copper (ii) phosphate. what is the empirical formula of the hydrated salt?

Which of these is a property of acid? A. They Taste Sour B. They Turn Litmus Paper Blue C. They Typically Cantain AN - Oh group D. They Feel Slipperey

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Before the initial explosion was the matter hot or cold

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A.) During an experiment, a student adds 2.90 g of CaO to 400.0 mL of 1.500 M HCl. The student observes a temperature increase of 6.00 °C. Assuming the solution/'s final volume is 400.0 mL, the density if 1.00 g/mL, and the heat capacity is 4.

Consider the ionic compound magnesium acetate. How many electrons does the magnesium ion have