# Tutor profile: Mackenzie N.

## Questions

### Subject: Basic Chemistry

How many lone pairs would be found in a water (H2O) molecule and what molecular geometry would it form?

Oxygen has 6 valence electrons based on its position on the periodic table. 6 dots would be drawn around the oxygen molecule. The two hydrogen atoms would bond to the oxygen, leaving two pairs of electrons without a bond. This results in two lone pairs in water. When a molecule has two bonded pairs and two lone pairs it creates a bent shape, so the molecular geometry of water is a bent shape.

### Subject: Biology

What is the order of classification?

The order of classification from largest to smallest is domain, kingdom, phylum, class, order, family, genus, species.

### Subject: Algebra

2(6x+9)-5(x+2)

To solve this problem, the distributive property is necessary for both parts. The first part 2(6x+9) would become 12x+18 because the 2 is distributed to both components in the parenthesis. The second part can be tricky since it is subtracting. It can be difficult to know where and where not to put the subtraction sign. I would link the subtraction sign with the 5. So when the -5 gets multiplied out through the parenthesis the results equal -5x-10. To complete the problem the two x values can be combined as well as the two non x values. So the answer to this problem would be 7x+8.

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