What is the molar mass of ca(clo4)2? (the 4 and 2 are subscripts)

a. 171.6 g/mol

b. 203.6 g/mol

c. 239.0 g/mol

d. 279.1 g/mol

Acontrol during an experiment. might change remains constant does not exist does change

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 amount of energy for a photon that has a 125 cm wavelength