<span>There are a number of ways
to express concentration of a solution. This includes molality. Molality is
expressed as the number of moles of solute per mass of the solvent. We calculate as follows:
0.200 mol I2 / kg CCl4 ( .750 kg CCl4 ) ( 253.809 g I2 / mol I2) = 38.07 g I2 needed
Hope this helps.
</span>
It is advisable to wear long sleeve when when a student is working in a chemistry lab so that to protect arms from lab chemicals. when someone enter the chemistry lab to wort or to study should be well prepared with appropriate gears and security measure to avoid injury.
<h3>
Answer:</h3>
0.699 mole CaCl₂
<h3>
Explanation:</h3>
To get the number of moles we use the Avogadro's number.
Avogadro's number is 6.022 x 10^23.
But, 1 mole of a compound contains 6.022 x 10^23 molecules
In this case;
we are given 4.21 × 10^23 molecules of CaCl₂
Therefore, to get the number of moles
Moles = Number of molecules ÷ Avogadro's constant
= 4.21 × 10^23 molecules ÷ 6.022 x 10^23 molecules/mole
= 0.699 mole CaCl₂
Hence, the number of moles is 0.699 mole of CaCl₂
The limiting reactant can be determined by calculating the
moles supplied / moles stoich ratio and the lowest is the limiting reactant.
Fe(CO)5 ratio = [6 g / 195.9 g/mol] / 1
Fe(CO)5 ratio = 0.0306
PF3 ratio = [4 g / 87.97 g/mol] / 2
PF3 ratio = 0.0227
H2 ratio = [4 g / 2 g/mol] / 1
H2 ratio = 2
<span>We can see that PF3 has the lowest ratio, so it is the
limiting reactant.</span>
Hey there! The answer to your first question is SILICON, Nickle has 28 protons, silicon has 14, 14+14=28. Its the only element thats adds up. I dont know about the 2nd one myself.
