19. Elements are pure substance because . a. all their atoms have different atomic numbers
b. all their atoms have the same atomic number
c. all their atoms are linked to atoms of other elements
d. everything looks the same
Use the attached sheet of conversion factors to answer the conversion questions.
20. A measurement of 10.70 mm would be converted to cm.
a. 0.00107 c. 107.0
b. 1.070 d. 1070.

Match the following vocabulary terms to their definitions. 1. amount of energy required to change 1 gram of material from the solid to the liquid state at its melting point 2. a measure of the kinetic energy of the particles of a substance 3. the amount of heat energy required to raise the temperature of 1 gram of liquid water from 14.5°c to 15.5°c 4. amount of energy required to change 1 gram of material from the liquid to the gaseous state at its boiling point 5. the amount of energy required to change 1 gram of a substance 1°c a. temperature b. latent heat of vaporization c. latent heat of fusion d. calorie e. specific heat

Ineed to find the answer of this question because i dont understand it

Which formula can be used to calculate the molar mass of hydrogen peroxide