Can someone help and answer this please? Doctors recommend taking vitamin (C) In winter days, How many moles of
Vitamin C (C. H.O.), are there in 528 g of Vitamin C?

a) moles
b) 2.75 moles
c) 3 moles
d)5 moles

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?