Calculate the number of atoms in 80.0g of calcium. [Relative atomic mass of Ca = 40]

List four observations that indicate that a chemical reaction may be taking place

The minerals found in bones are deposited by living cells called

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.