I'm assuming false but really have no clue
Answer:
0.302L
Explanation:
<em>...97.1mL of 1.21m M aqueous magnesium fluoride solution</em>
<em />
In this problem the chemist is disolving a solution from 1.21mM = 1.21x10⁻³M, to 389μM = 389x10⁻⁶M. That means the solution must be diluted:
1.21x10⁻³M / 389x10⁻⁶M = 3.11 times
As the initial volume of the original concentration is 97.1mL, the final volume must be:
97.1mL * 3.11 = 302.0mL =
0.302L
Answer:

Explanation:
1. Number of electrons

2. Number of protons

3. Identify the ion
An atom with 26 protons is iron, Fe.
A neutral atom of iron would have 26 electrons.
The ion has only 24 electrons, so it has lost two. The ion must have a charge of +2.

Answer:
9.01%
Explanation:
The following data were obtained from the question:
Mass of sodium nitrate, NaNO3 = 56.5g
Mass of solution = 627g
The percentage composition of sodium nitrate, NaNO3 in the solution can be obtained as follow:
Percentage composition of NaNO3 = Mass of NaNO3/mass of solution x 100
Percentage composition of NaNO3 = 56.5/627 x 100 = 9.01%
Therefore, the percentage composition of sodium nitrate, NaNO3 in the solution is 9.01%
Answer: There are few simple rules to follow.
(1) The atomic number is equal to the number of protons.
Z
= number of protons
(2) In neutrally charged elements, the number of electrons is the same as the number of protons.
Z
= number of protons = number of electrons (no charge)
Otherwise, positive charge means that the element lost an electron and negative charge means it gained an electron.
(3) The atomic mass is equal to the sum of the number of protons and number of neutrons.
A
= number of protons + number neutrons
or
A
=
Z
+ number neutrons
So if you say that
Z
= 20 and
A
= 40, then
A
=
Z
+ number neutrons
40 = 20 + number of neutrons
40 - 20 = number of neutrons
Therefore,
number of neutrons = 20
Explanation: