To calculate the mean, you add up all of the data values, and then divide that sum by the *number* of values.
For instance, if you wanted to find the mean score at a home run derby, and you’re given the following numbers for home runs scored by each player:
5, 4, 6, 5, 3, 1
You could calculate the mean by adding all of the score up
5 + 4 + 6 + 5 + 3 + 1 = 24
And dividing by the number of hitters (in this case, 6)
24 / 6 = 4
So the *mean score* of the home run derby would be 4.
The concentration may be expressed as % m/m, this is the mass of ions in 100 mass units of solution, whose formula is:
% m/m = [mass of ions / mass of solution]*100
Then,
%m/m = [8.5*10^ -3 grams of calcium ions] / [490 grams of solution] * 100 =
% m/m = 1.74 * 10^ -5 %
Answer: 1.74 * 10 ^ -5 %
Answer:
8.9 mg/l
Explanation: Temp doesnt matter so throw that out automatically then your equation is;
S1/P1=S2/P2
We are looking for S2 and that equation is;
S2=S1*P2/P1 and that is S2=22.25*1/2.5
A little bit of simple math and you get your answer: 8.9 mg/l
Answer:
element having 2+ valence electrons can transfer its more than one electron that is 2 electron completely.
Explanation:
- Group IIA have 2+ valency and two electrons in its valance shell.
- Its Electropositivity is high and have the tendency to donate it two electrons.
- Element of IIA form ionic with most electronegative element.
Examples:
Cu²⁺, Mg²⁺, Sr²⁺ are examples having 2+ valance electron
one of the following is examples of element that have 2+ valence electrons
MgCl₂
Atomic number of Magnesium (Mg) is 12
Electronic Configuration of Mg:
1s², 2s², 2p⁶, 3s²
or
K =2
L = 8
M = 2
So, it have to give its 2 electrons to form a stable compound.
Similarly
Chlorine atomic number is 17
Electronic Configuration of Chlorine:
1s², 2s², 2p⁶, 3s², 3p⁵
or
K =2
L = 8
M = 7
So, it have to gain one electrons to form a stable compound and complete its octet.
So,
Two chlorine atom as a molecule gain 2 electrons from Mg²⁺ atom
So one Mg²⁺ and 2 Cl⁻ atoms form an ionic bond
where in this ionic bond Mg²⁺ transfer its 2 valence electron completely and chlorine molecule accept 2 electrons.
Cl-----Mg------Cl
So the Answer is
element having 2+ valence electrons can transfer its more than one electron that is 2 electron completely.