4.648 gm of solute is needed to make 37.5 mL of 0.750 M KI solution.
Solution:
We will start with the Molarity
Also we know 1000 ml = 1 L
Therefore 37.5 ml by 1000ml we obtained 0.0375L
Equation for solving mole of solute
Now, multiply 0.750M by 0.0375
Substitute the known values in the above equation we get
Also we know that Molar mass of KI is 166 g/mol
So divide the molar mass value to get the no of grams.
So 4.648 gm of Solute is required for make 37.5 mL of 0.750 M KI solution.
The 2.5 x 10²¹ molecules of CH₃OH have 0.00415 moles.
<h3>What is the mole concept?</h3>The number of moles is given by
When given mass = molar mass of a substance, then no of moles is equal to 1 which is equivalent to 6.022 x 10²³.
We also know,
1 mole has 6.022 x 10²³ molecules of CH₃OH
According to the mole concept,
6.022 x 10²³ molecules of CH₃OH is equal to 1 mole
2.5 x 10²¹molecules of CH₃OH is equal to moles
Thus, 2.5 x 10²¹molecules of CH₃OH are equal to 4.15 x 10⁻³ moles or 0.00415 moles
Learn more about the mole concept:
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