Answer:
Number of moles = 0.05 mol
Explanation:
Given data:
Mass of Pb = 10.5 g
Number of moles of Pb = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of Pb is 207.2 g/mol.
Now we will put the values in formula.
Number of moles = 10.5 g/207.2 g/mol
Number of moles = 0.05 mol
Answer: dilute
Explanation:
A concentrated solution which is used to prepare solutions of lower concentrations by diluting it with addition of water.
A dilute solution is one which contains lower concentration.
Using Molarity equation:
=concentration of stock solution = 0.150 mol/L
= volume of stock solution = 10.0 ml
= concentration of dilute solution = ?
= volume of dilute solution = (10.0+90.0) ml = 100.0 ml


As the concentration is less than the original concentration, the solution is termed as dilute.
It depends, for example, it is quite important to know the Kelvin scale (i.e 0 degrees Celsius is 273 K and -273 degrees Celsius is 0 K ) when dealing gases. But I don't know other situations where you would need to know other temperature scales.
Hope this helps and also if you are using Fahrenheit 1 Fahrenheit is -17.22 degrees Celsius
The mass, in grams, of the sample of methanol (CH₃OH) is 64 grams.
<h3>How we calculate mass from moles?</h3>
Mass of any substance can be calculated by using moles as:
n = W/M, where
W = required mass
M = molar mass
In the question that:
Moles of methanol = 2mole
Molar mass of methanol = 32g/mole
On putting these values in the above equation, we get
W = n × M
W = 2mole × 32g/mole = 64g
Hence, 64 grams is the mass of the sample.
To know more about moles, visit the below link:
brainly.com/question/15374113