How many particles are in 9.34 g of methane?

According to the tide table below what time of day will the highest tide occur?

Agas diffuses 1/7 times faster than hydrogen gas (h2). what is the molar mass of the gas? 100.10 g/mol 98.78 g/mol 86.68 g/mol 79.98 g/mol

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.