Answer:
Molar mass = 151.9 g/mol
Explanation:
The molar mass of a compound is obtained by adding u the individual atomic masses in the compound. The unit is g/mol.
In FeSO4, we have one Fe, one S and 4 O.
The atomic masses are given as follows;
Fe = 55.845 u
S = 32.065 u
O = 15.999 u
Molar mass = ( 1 * Fe) + (1 * S) + (4 * O)
Molar mass = (1 * 55.854 ) + ( 1 * 32.065) + (4 * 15.999)
Molar mass = 151.915 g/mol
In four significant figures;
Molar mass = 151.9 g/mol
Explanation:
The given data is as follows.
Weight of solute = 75.8 g, Molecular weight of solute (toulene) = 92.13 g/mol, volume = 200 ml
- Therefore, molarity of toulene is calculated as follows.
Molarity = 
= 
= 4.11 M
Hence, molarity of toulene is 4.11 M.
- As molality is the number of moles of solute present in kg of solvent.
So, we will calculate the molality of toulene as follows.
Molality = 
= 
= 8.6 m
Hence, molality of given toulene solution is 8.6 m.
- Now, calculate the number of moles of toulene as follows.
No. of moles = 
= 
= 0.8227 mol
Now, no. of moles of benzene will be as follows.
No. of moles = 
= 
= 1.2239 mol
Hence, the mole fraction of toulene is as follows.
Mole fraction = 
= 
= 0.402
Hence, mole fraction of toulene is 0.402.
- As density of given solution is 0.857
so, we will calculate the mass of solution as follows.
Density = 
0.857
=
(As 1
= 1 g)
mass = 171.4 g
Therefore, calculate the mass percent of toulene as follows.
Mass % = 
= 
= 44.22%
Therefore, mass percent of toulene is 44.22%.
Answer:
C. Lose three electrons to have a full outer shell
Explanation:
Al is in Group 13 of the Periodic Table, so it has three valence electrons.
It must either lose three electrons or gain five to achieve a stable octet.
It is easier to lose three electrons than it is to gain five, so Al loses three electrons.
D. is wrong, for the same reason.
A. is wrong. If Al lost three electrons, it would be breaking into a stable inner shell.
C. is wrong. Al is a metal, so it will lose electrons in a reaction.
Answer:
B
Explanation:
because dogs don't do c,The owner trains the dog to do a,d and b is naturally learned
The order of placement of the elemnts on the modern Periodic Table is determinated by:
1)atomic number (Z=number of protons).