Answer:
1.38 x atoms
Explanation:
To get grams to atoms/molecules/particles we need to first convert grams > moles > atoms. This also applies in the other direction, where you have moles as that stepping stone.
Some key information we need:
Magnesium's molar mass= 24g/mol
Avogadro's Number= 6.022 x atoms
Where there is 1 mol per 6.022 x atoms
*This maybe be something you want to memorize.
Grams to moles using molar mass , then to atoms using avogadro's number.
55g Mg x x = 1.38 x atoms
1s2 2s2 2p6 3s2 3p6 4s2 is the electron configuration for Calcium
The traditional calcium atom has twenty protons and twenty electrons making it neutral.
The calcium in the pic is a calcium ion so the number of protons and electrons are not equivalent.
Since it's 2+ that means the ion is positively charged and for that to happen electrons are away.
So 20-2=18
There are 18 electrons
hope it's help you ok have a good day
Answer:
16.52 lb NaCl will be in the tank at the end of 3 hours.
Explanation:
Let s(t) = gal of NaCl in a container at time t (in minutes).
s'(t) = The rate at which the amount of gal of NaCl in the container is changing.
s'(t) = Rate of NaCl going in - Rate of NaCl going out
By variable separable method we get
Integrate both sides.
100 Ib of NaCl are initially dissolved in 600 gal of a NaCl solution in a container. it means s(0)=100.
Therefore the required function is
.... (1)
We need to find the amount of NaCl will be in the tank at the end of 3 hours.
3 hours = 180 minutes.
Substitute t=180 in equation (1).
Therefore, 16.52 lb NaCl will be in the tank at the end of 3 hours.