<span>iron has 26 protons and 30 neutrons are in the nucleus</span>
Answer:
The molarity (M) of the following solutions are :
A. M = 0.88 M
B. M = 0.76 M
Explanation:
A. Molarity (M) of 19.2 g of Al(OH)3 dissolved in water to make 280 mL of solution.
Molar mass of Al(OH)3 = Mass of Al + 3(mass of O + mass of H)
= 27 + 3(16 + 1)
= 27 + 3(17) = 27 + 51
= 78 g/mole
= 78 g/mole
Given mass= 19.2 g/mole
Moles = 0.246
Volume = 280 mL = 0.280 L
Molarity = 0.879 M
Molarity = 0.88 M
B .The molarity (M) of a 2.6 L solution made with 235.9 g of KBr
Molar mass of KBr = 119 g/mole
Given mass = 235.9 g
Moles = 1.98
Volume = 2.6 L
Molarity = 0.762 M
Molarity = 0.76 M
They have a different amount of neutrons.
If you'd like the full working, here it is:
I calculated this by using the formula triangle.
Mass
Number Formula
Of moles Mass
To calculate the number if moles in a substance, you need to divide the Mass by the Formula mass. You get the formula mass by adding the atomic masses of the elements in the compound together. In this situation, H2O, it would be two hydrogen molecules plus one oxygen molecule which is 2 + 16. This is because the atomic mass of Hydrogen is 1 and the atomic mass of Oxygen is 16.
Now that we have the Formula mass we can go ahead and do the calculation since we already have the Mass. You do as follows:
Mass divided by Formula mass which is in this case - 25 divided by 18
By doing this calculation you will get the answer which is 1.38 moles which can be rounded to 1.4
Hope this helps :)
If in a redox reaction oxidation state of elements decreases or looses electron(s), the element is said to be oxidized. Hope this helps you!
