Question 9. The first one is the smallest. Anything with a negative exponent is going to be less than 1, the .00000241. The exponent tells you the number of zeroes to the right of the decimal point. Farther to right gets smaller and smaller.
Question 10. The last one is true. If the last digit is smaller than 5, drop the digit, and do not change. (If it is a 5 or larger, the digit before it would round up)
<span>M(NO3)2 ==> [M2+] + 2 [NO3-]
0.202 M ==> 0.202 M
M(OH)2 ==> [M2+] + 2[OH-]
5.05*10^-18 ===> s + [2s]^2
5.05*10^-18 ===> 0.202 + [2s]^2
5.05*10^-18 = 0.202 * 4s^2
4s^2 = 25*10^-18
s^2 = 6.25*10^-18
s = 2.5*10^-9
So, the solubility is 2.5*10^-9</span>
The earth has the moon captured in its gravity. this keeps the moon in an elliptical orbit
Answer: 8.691 mols of CO₂
Explanation:
To find the number of moles in a given grams, you want to use the molar mass.
Let's first find the molar mass of CO₂.
Carbon's molar mass is 12.011 g/mol
Oxygen's molar mass is 15.999 g/mol
To find molar mass of CO₂, we want to add up the molar mass of carbon and oxygen. Remember, there are 2 Oxygens so we need to mulitply that by 2.
12.011+2(15.999)=44.009 g/mol
Now that we have molar mass, we can convert 382.5 g to mols.

There are about 8.691 mols of CO₂.
Answer:
λ = 6.5604 x 1016 nm
Explanation:
Given Data:
The energy of the red line in Hydrogen Spectra = 3.03 x 10-19
Formula to calculate Wave length
E= hv
Where E is Energy
h is Planks Constant = 6.626 x 10–34 J s
v is frequency
In turn
v= c/ λ
where c is speed of light = 3.00 x 108 m s–1
λ is wavelength = to find
Solution:
Formula to be Used:
E= hv………………………… (1)
Putting the value v in equation 1
E= h c/ λ…………………… (2)
Put the value in equation 2
3.03 x 10-19 J = (6.626 x 10–34 J s) x (3.00 x 108 m s–1) / λ ……………………….(3)
By rearranging equation 3
λ = (6.626 x 10–34 J s) x (3.00 x 108 m s–1) /3.03 x 10-19 J
λ = 6.5604 x 107 m
The answer is in “m”
So we have to convert it into nm
So for this to convert “m” to “nm” multiply the answer with 109
λ = 6.5604 x 107 x 109
λ = 6.5604 x 1016 nm