How do you determine the mass number of an atoms

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

Which atom or ion is the largest? 0 a. 0 0 0 0 e. li

What is the percentage composition of carbon in the compound ch4