Answer: two elements and three atoms
Explanation:
An element is the simplest substance and hence cannot be broken down using chemical reactions.
Magnesium chloride
is an ionic compound formed by the transfer of electrons from element magnesium (Mg) to element chlorine (Cl) where Magmesium forms a cation
by losing two electrons and chlorine forms an anion
by gaining electron.
There are 3 atoms in Magnesium chloride
which include one atom of magnesium (Mg) and two atoms of chlorine (Cl).
PH is defined as the negative log of Hydrogen ion concentration. Mathematically we can write this as:
![pH=-log[H^{+}]=-log[H_{3}O]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%7B%2B%7D%5D%3D-log%5BH_%7B3%7DO%5D%20%20)
We are given the concentration of

. Using the value in formula, we get:
Therefore, the pH of the solution will be 3.745
The amount of matter in an object is said to be its mass. The SI base unit of mass is kilograms i.e.
.
The mass of the object =
(given)
For converting lbs to kg:

So, 
Hence, the mass of
object in kilograms is
.
Molality is defined as the number of moles of solute in 1 kg of solvent.
molality of solution to be prepared is 0.50 molal
this means that in 1000 g of water there should be 0.50 mol of NaCl
if 1000 g of water should contain - 0.50 mol
then 750.0 g of water requires - 0.50 mol/kg x 0.750 kg = 0.375 mol
mass of NaCl in 0.375 mol - 58.5 g/mol x 0.375 mol = 21.9 g
therefore a mass of 21.9 g of NaCl is required
Answer:
for 1 Litre(1000 ml) of 1x TBE
10.8 g Tris
5.5 g Boric acid
4 ml 0.5 M EDTA (pH 8.0)
900 ml distilled water
Adjust volume to 1 Liter.
<u>so for 250 ml divide everything by 4</u>
2.7 g Tris
1.37 g Boric acid
1 ml 0.5 M EDTA (pH 8.0)
225 ml distilled water
Adjust volume to 250 Ml