So what we know:
-Atomic Mass = Protons + Neutrons
-Atomic Number is the number of protons
Magnesium's atomic number is 12, so the natural occurring isotope for magnesium is Mg-12 (12 protons and 12 neutrons). Added up we have an atomic mass of 24 amu. Which means if we added one neutron in Mg-13, our atomic mass would be 25 amu.
We can use the equation:
(amu of isotope 1)x + (amu of isotop 2)(x-1) = Average atomic mass
where isotope 1 is the fractional abundance we're solving for.
Plugged in it looks like this:
24x + 25(1-x) = 24.3
Now to solve for x:
24x + 25 - 25x = 24.3
-x + 25 = 24.3
-x = -.7
x = .7
So in this case, the fractional abundance of Mg-12 would be .7, or 70%.<span />
Only an apple will float when placed in water.
An object will float in water if its density is <em>less than that of water</em> (1.0 g/mL).
An object will sink in water if its density is <em>greater than that of water</em>.
Thus, solid objects made of <em>gold, iron, or rubber</em> will all sink in water.
this is the answer of your question .
<em>Hope</em><em> </em><em>it</em><em> </em><em>helped </em><em>you</em>
Answer: 35.4 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

where,
Molality = 2.65
n= moles of solute =?
= volume of solution in ml = 445 ml
Putting in the values we get:


Mass of solute in g=
Thus 35.4 grams of
is needed to prepare 445 ml of a 2.65 m solution of
.