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 />
Answer:
Moles of BCl₃ needed = 0.089 mol
Explanation:
Given data:
Moles of BCl₃ needed = ?
Mass of HCl produced = 10.0 g
Solution:
Chemical equation:
BCl₃ + 3H₂O → 3HCl + B(OH)₃
Number of moles of HCl:
Number of moles = mass/molar mass
Number of moles = 10.0 g/ 36.46 g/mol
Number of moles = 0.27 mol
Now we will compare the moles of HCl with BCl₃.
HCl : BCl₃
3 : 1
0.27 : 1/3×0.27 = 0.089 mol
Answer: The workdone W = 505J
Explanation:
Applying the pressure-volume relationship
W= - PΔV
Where negative sign indicates the power is being delivered to the surrounding
W = - 1.0atm * ( 5.88 - 0.9)L
= - 1.0atm * (4.98)
W = -4.98 atmL
Converting to Joules
1atmL = 101.325J
-4.98atmL = x joules.
Work done in J = -4.98 * 101.325
W= -505J
Therefore the workdone is -505J
Answer : The correct option is, (A)
because one of each is produced every time an
transfers from one water molecule to another.
Explanation :
As we know that, when the two water molecule combine to produced hydronium ion and hydroxide ion.
The balanced reaction will be:

Acid : It is a substance that donates hydrogen ion when dissolved in water.
Base : It is a substance that accepts hydrogen ion when dissolved in water.
From this we conclude that, the hydrogen ion are transferred from one water molecule to the another water molecule to form hydronium ion and hydroxide ion. In this reaction, one water molecule will act as a base and another water molecule will act as an acid.
Hence, the correct option is, (A)
Answer:
B
Explanation:
catches fire easily, there is a chemical in the substance that reacts to the flame, and a key to it being a chemical property is when exposed to other substances, there is a chemical in the other substances that makes it chemically react