Answer:
The number of mol is: 0, 042 mol in 4 grams of MgCl2
Explanation:
We calculate the weight of 1 mol of MgCl2:
Weight 1mol of MgCl2= weight Mg + (weight Cl)x 2=
24, 3 grams + 2 x 35, 5 grams = 95, 3 grams/mol MgCl2
95, 3 grams------1 mol MgCl2
4 grams -------x = (4 grams x1 mol MgCl2)/ 95, 3 grams= 0, 04197 mol MgCl2
Answer:
7.12 mm
Explanation:
From coulomb's law,
F = kqq'/r².................... Equation 1
Where F = force, k = proportionality constant, q and q' = The two point charges, r = distance between the two charges.
Make r the subject of the equation,
r = √(kqq'/F).......................... Equation 2
Given: q = q' = 75.0 nC = 75×10⁻⁹ C, F = 1.00 N
Constant: k = 9.0×10⁹ Nm²/C².
Substitute into equation 2
r = √[ (75×10⁻⁹ )²9.0×10⁹/1]
r = 75×10⁻⁹.√(9.0×10⁹)
r = (75×10⁻⁹)(9.49×10⁴)
r = 711.75×10⁻⁵
r = 7.12×10⁻³ m
r = 7.12 mm
Hence the distance between the point charge = 7.12 mm
Using evidence to support explanations is a good practice because it proves that what you are explaining can be verified.
The correct answer is this one: "the number of electrons that are involved in the bonding of the molecule." Lewis structures help us understand the number of electrons that are involved in the bonding of the molecule. It also helps us know the shape of the molecule, its reactivity and its interaction with other molecules.
<u>Answer:</u> The correct answer is Option C.
<u>Explanation:</u>
We are given some polyatomic ions with their oxidation states. Polyatomic ions are defined as the ions which are formed from more than 2 atoms.
We need to find out the chemical formula for ammonium phosphate.
For this, the polyatomic ions used are:
Ammonium ion - 
Phosphate ion - 
By using criss-cross method, the oxidation state of the ions are exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.
Thus, the chemical formula for this compound is 
Hence, the correct answer is Option C.