Answer: Option A) 83.9g
Explanation:
KCl is the chemical formula of potassium chloride.
Given that,
Amount of moles of KCl (n) = ?
Volume of KCl solution (v) = 0.75L
Concentration of KCl solution (c) = 1.5M
Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence
c = n / v
make n the subject formula
n = c x v
n = 1.5M x 0.75L
n = 1.125 mole
Now given that,
Amount of moles of KCl (n) = 1.125
Mass of KCl in grams = ?
For molar mass of KCl, use the molar masses of:
Potassium, K = 39g;
Chlorine,Cl = 35.5g
KCl = (39g + 35.5g)
= 74.5g/mol
Since, amount of moles = mass in grams / molar mass
1.125 mole = m / 74.5g/mol
m = 1.125 mole x 74.5g/mol
m = 83.81g
Thus, 83.9 grams of KCl are needed to prepare 0.750 L of a 1.50 M solution in water
Answer:
Explanation:
Data provided as per the question below:-
Wavelength = 430.nm
The computation of the frequency of the light is shown below:-
Frequency = Velocity of light ÷ Wavelength
The Velocity of light =
Wavelength = 430 nm = m
Frequency =
=
Therefore for determining the frequency we simply applied the above formula.
Explanation:
2,3-diethyl hexane
At first we select a long chain.
Then, we number that chain from that side where substituent position is closer.
Then, we write it's IUPAC name
Position of substituent + substituent name + chain name + suffix
Here,
2,3 + -diethyl + hex + -ane
= 2,3-diethyl hexane
A chemical change is characterized of the formation of new substances or a chemical reaction. There are a number of observations that we can see if this type of change happens. One would be the formation of gas bubbles, this indicates that one of the products is a gas. Another observation would be a formation of a precipitate in the solution, it would indicate that the new solid formed is not soluble in the solution. A permanent color change in the solution would also indicate a chemical change because it may be that the new substance that is formed has its own distinct color when in solution.