Which of the following has the largest atomic radius: calcium, beryllium, barium, and strontium

What is the standard unit of measure for acceleration?

How many grams of aluminum will there be in 98g of al2o3?

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?