Answer:
0.133 M
Explanation:
The volume of the solution is given, so in order to find concentration, the number of moles must be found, since C = n/V.
The balanced reaction equation is:
HI + KOH ⇒ H₂O + KI
Thus, the moles of KOH added to neutralize all of the HI will be equal to the moles of HI that must have been present.
The amount of KOH that was added is calculated as follows.
n = CV = (0.145 mol/L)(45.7 mL) = 6.6265 mmol KOH = 6.6265 mmol HI
Since HI and KOH are related in a 1:1 molar ratio, the same amount of HI must have been present.
Finally, the concentration of HI is calculated:
C = n/V = (6.6265 mmol) / (50.0 mL) = 0.133 mol/L = 0.133 M
Given:
volume of 0.08 m³
density of 7,840 kg/m³
Required:
force of gravity
Solution:
Find the mass using density
equation.
D = M/V
M = DV
M = (7,840 kg/m³)(0.08 m³)
M = 627.2kg
F = Mg
F = (627.2kg)(9.8m/s2)
F = 6147N
<u>Answer:</u> The correct answer is Option 3.
<u>Explanation:</u>
All the radioisotope decay processes follow first order kinetics.
Rate law expression for first order kinetics is given by the equation:

where,
k = rate constant = ?
t = time taken for decay process = 8.32 seconds
a = initial amount of the reactant = 80 mg
a - x = amount left after decay process = 20 mg
Putting values in above equation, we get:

The equation used to calculate half life for first order kinetics:

where,
= half life of the reaction = ?
k = 
Putting values in above equation, we get:

Hence, the correct answer is Option 3.
Answer:
<h2>Molarity = 7 mol / L</h2>
Explanation:
Since the mass of NaCl and it's volume has been given we can find the molarity by using the formula
<h3>

</h3>
where
C is the molarity
m is the mass
M is the molar mass
v is the volume
From the question
v = 0.5 L
m = 205 g
We must first find the molar mass and then substitute the values into the above formula
M( Na) = 23 , M( Cl) = 35.5
Molar mass of NaCl = 23 + 35.5 =
58.5 g/mol
So the molarity of NaCl is

C = 7.00854
We have the final answer as
<h3>Molarity = 7 mol / L</h3>
Hope this helps you
Where is the picture to this?