# Tutor profile: Brandon H.

## Questions

### Subject: Chemistry

What is the difference between the atomic number and the atomic mass on the periodic table?

The atomic number is the number of protons that the element has. For example, the atomic number of carbon is 6 because a carbon atom contains 6 protons. The atomic mass of an element is the total mass (protons, neutrons, electrons) of the element. The mass of an atom is made almost entirely of it's protons and neutrons however because the mass of an electron is almost negligible. So going back to carbon, the atomic mass is 12.01amu. By knowing both the atomic number and the atomic mass, you can figure out how many protons (based on the atomic number) and how many neutrons (subtract the atomic number from the atomic mass) are present in an atom. So again carbon we saw from the atomic number that it has 6 protons, and is we subtract that from the atomic mass (12.01) we find that there are 6 neutrons

### Subject: Biology

What are the differences between Eukaryotic and Prokaryotic cells?

The differences between the two types of cells are mostly structural. Prokaryotic cells have their genetic material freely flowing around in the cytosol, while Eukaryotic cells have a membrane-bound nucleus that holds all the genetic material in one location. SImilarly, eukaryotic cells have membrane-bound organelles (such as the mitochondria and golgi apparatus) that localize certain processes, while prokaryotes lack these membrane-bound organelles. Additionally, methods of cellular division vary between prokaryotes and eukaryotes, While eukaryotes divide via mitosis, prokaryotes use the method of binary fission

### Subject: Algebra

Why is Equation 1 equivalent to Equation 2? Equation 1: 3(2x−4) =−18 Equation 2: 6x−12 =−18?

The equations are equivalent based on the Distributive Property taking precedent over the subtraction in the parenthesis of Equation 1. If you look at the right side of Equation 1, you'll see a 3 outside the parenthesis: 3(2x-4)= -18 The numbers in the parenthesis are multiplied by the 3 on the outside giving us the following result [ (3*2x) - (3*4) ] = -18 Because of PEMDAS, multiplication takes precedence over subtraction so it must be performed first, giving us Equation 2 6x-12= -18

## Contact tutor

needs and Brandon will reply soon.