Answer: A) polar molecule
Explanation: Polar molecules are molecules which contain atoms of different electronegativities.
Non polar molecules are molecules which contains atoms of same electronegativities.
Water is a polar covalent molecule formed by unequal sharing of electrons. Oxygen being more electronegative tend to keep the electron pair towards itself thus generating a partial negative charge. The hydrogen acquire a partial positive charge thus resulting in a polar molecule.
The bent shape is due to repulsion between lone pairs and bond pairs of electrons.
Answer:
The percentage yield of water is 66.67%.
Explanation:

Mass of oxygen gas = 100 g
Moles of oxygen gas = 
According to reaction, 1 mole of oxygen gives 2 moles of water, then 3.125 moles of oxygen will give:

Mass of 6.25 moles of water :
6.25 mol × 18 g/mol = 112.5 g
Theoretical yield of water = 112.5 g
Experimental yield of water = 75 g
Percentage yield :


The percentage yield of water is 66.67%.
4)
a) Natural selection will work negatively against rabbits that only eat berries as the drought is preventing berries from growing. It wont have any negative impact on rabbits that only eat grass as the grass is still surviving.
b) The statement ‘population has variations’ is backed up by the fact that the rabbits eat different things. They aren’t all the same. The statement ‘some variations are favorable’ is backed up by the fact that the rabbits that only eat grass are able to survive the drought. Their variation in eating grass instead of berries let’s them live. The statement ‘a population will change over time’ is backed up by the fact that the rabbits that only eat berries will die out. This will not only change the size of the population but going forward will create a population that has more rabbits that eat only grass on account of natural selection.
Answer:
O(Oxygen)
Explanation:
2+2+4=8
And the eighth element of the periodic table is Oxygen
Answer:
146.3g NaCl (mol NaCl/58.44g NaCl) = 2.50 mol NaCl
1.5M NaCl = 1.5 mol NaCl / 1 L = 2.5 mol NaCl / x L, solve for x
x L = 2.5 mol NaCl / 1.5 mol NaCl = 1.66 L
It gives the answer and all the working.
To put it another way:
Dividing the amount required by the molar mass
we quickly see that 2.5 moles are required.
One litre of 1.5 molar solution gives 1.5 moles
we need a further mole, which is 2/3 of 1.5 so 2/3 of a litre.