Atomic number is protons + electrons
Mass number is protons + neutrons
So to calculate the number of neutrons, you do
atomic number - atomic mass
31 - 84 = - 53
Answer:
i dunno if this helps :(
Explanation:
Heat is energy transferred between substances or systems due to a temperature difference between them, according to Energy Education. As a form of energy, heat is conserved, i.e., it cannot be created or destroyed. It can, however, be transferred from one place to another.
It’s c or b I think I’m not sure
Answer is: step 3 would be placed C.
This is example of chemical change (chemical reaction), because new substances are formed (gas is emitted), the atoms are rearranged.
Physical property can be observed and measured without any changes in molecular composition. The same substance is present before and after the psysical change, just with different form or state of matter.
Chemical reaction: powder + water → new substance + gas.