Answer:

I'm just in jss2 but I read physics. this is what I think
Answer:
She will use one 2 as a subscript.
Explanation:
Nitrogen is a chemical element with the symbol "N" and has an atomic number of 7. Thus, it is found in group (5) of the periodic table and as such it has 5 electrons in its outermost shell. Therefore, nitrogen has two (5) valence electrons.
On the other hand, oxygen has an atomic number of 8 and with the symbol "O."
When nitrogen and oxygen react chemically, they produce a compound known as nitrogen dioxide
In this scenario, Jenny is studying a compound that has two oxygen atoms and one nitrogen atom. Therefore, the statement which describes the subscripts she will use to write the chemical formula is, she will use one 2 as a subscript.

Where: 2 represents the subscript of oxygen.
CaS is the empirical formula of the compound between calcium and sulphur that has the percent composition 55.6.
When percentages are given, we take a total mass of 100 grams.
Therefore the mass of each element is equal to the percentage given.
Mass of Ca = 55.6 g (given) of
S Mass = 44.4 g (100 - 55.6 = 44.4)
Step 1: Convert the given mass to moles.
moles Ca = given mass Ca / molar mass Ca
moles = 55.6 / 40 = 1.39 moles
mol S = specific mass S / molar mass S
mol = 44.4 / 32 = 1.39 mol
Step 2: Divide the molar ratio of each molar value by the smallest number of moles calculated.
For Ca = 1.39 / 1.39 = 1
For S = 1.39 / 1.39 = 1
The ratio of Ca : S = 1:1
Hence the empirical formula of the given compound will be CaS.
Learn more about empirical formula here : brainly.com/question/1496676
#SPJ4
Answer:
B and B
Explanation:
Question 1:
The distance is a unit of length, such as miles, meters, kilometers
The correct answer for this question would be 8m
Question 2:
Speed has a unit of length per unit of time.
The correct answer for this would be meters per second
-Chetan K
The answer is; Irregular.