The correct answer is option B. Dirty water is a mixture of solid particles and liquid. It is both a mixture and pure substance.
The dirty water sample has both gravel and liquid water in it. After filtration the gravel is removed so the water sample looks clearer than before filtration. Liquid water is a pure substance because it is a compound that is made up of elements hydrogen and oxygen. Now the gravel is only physically combined with the liquid water, thus giving the water sample properties of a mixture. And like any mixture, gravel is physically separated through filtration from the liquid water.
Thus the water sample of the chemists is both a mixture and pure substance.
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.
Answer:
it would be the second choice
The heat released by cpmolete the combustion of organic products with oxygen is called heat of combustion.
Here 1 mol of CH4 realesed 802.3 KJ
To emit 264 kJ you multiply you need (1 mol of CH4/802.3 kJ)* 264 kJ = 0.329 mol of CH4
The molar mass, MM, of CH4 is 12 g/mol + 4*1g/mol = 16 g/mol
The to obtain the mass multiply the number of moles times the molar mass:
mass = n * MM = 0.329mol * 16g/mol = 5.26 grams
Answer: 5.26 grams
