How many moles are in 2.70 x 1024 particles?

How hot is the suns corona? (integrated science)

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

What is the effect of returning nuclear reactor cooling water back into bodies of water?