If the pOH of a nitric acid (HNO3) solution is measured as 11, what is the concentration of HNO3 solution? 2 × 10-3 M
1 × 10-3 M
1 × 10-11 M
3 × 10-3 M

An alloy contains 66 g of pure zinc. what is the percentage of zinc in the alloy? express your answer to two significant figures and include the appropriate units.

How many atoms are in 2 moles of phosphorus?

In what way do investigations build scientific knowledge? the results of investigations lead to questions that cannot be tested. they reflect the opinions and social values of scientists, ensuring valid information. the results of investigations lead to new questions, which lead to new investigations. they are not influenced by the research of earlier scientists, so they are able to address gaps in understanding.i