I believe the answer is D
The decoders of the DNA messege
Answer:
0.077 M
Explanation:
Molarity is the representation of the solution.
Molarity:
It is amount of solute in moles per liter of solution and represented by M
Formula used for Molarity
M = moles of solute / Liter of solution . . . . . . . . . . (1)
Data Given :
The concentration of half normal (NaCl) saline = 0.45g / 100 g
So,
Volume of Solution = 100 g = 100 mL
Volume of Solution in L = 100 mL / 1000
Volume of Solution = 0.1 L
molar mass of NaCl = 58.44 g/mol
Now to find number of moles of Nacl
no. of moles of NaCl = mass of NaCl / molar mass
no. of moles of NaCl = 0.45g / 58.44 g/mol
no. of moles of NaCl = 0.0077 g
Put values in the eq (1)
M = moles of solute / Liter of solution . . . . . . . . . . (1)
M = 0.0077 g / 0.1 L
M = 0.077 M
So the molarity of half-normal saline solution (0.45% NaCl) = 0.077 M
The molar volume of a gas at STP occupies <u>22.4 L.</u>
Option D
<u>Explanation:</u>
To find the volume of 1 mole of a gas at STP, we use the Ideal Gas Law. It is the general gas equation which gives the relation to the measurable quantities to an ideal gas as below,
P (pressure) × V (volume) = n (number of moles) × R (the gas constant) × T (temperature in Kelvin)
STP = 1 atm of pressure and 273 K for temperature
P = 1 atm
V = ?
n = 1 mole
R = 0.0821 atm L/mol K
T = 273 K
Using the equation,
By substituting the above values, in the equation,
V = 22.38 L
Answer:
8.55 moles
Explanation:
The formula for calculating molarity is moles of solute divided by liters of solution. In this case:
moles. Hope this helps!
