Answer:
2.67 g/mL
Explanation:
Initial Volume of water = 10.0 mL
Final Volume pf water = 15.46 mL
Mass = 14.74g
Density = Mass / Volume of aluminium
Volume of aluminium = Final Volume of water - Initial Volume of water = 15.46 - 10 = 5.46mL
Density = 14.74 / 5.46 = 2.67 g/mL
Answer:
Explanation:
Given that:
From equation (3) , multiplying (-1) with equation (3) and interchanging reactant with the product side; we have:
Multiplying (2) with equation (4) ; we have:
From equation (1) ; multiplying (-1) with equation (1); we have:
From equation (2); multiplying (3) with equation (2); we have:
Now; Adding up equation (5), (6) & (7) ; we get:
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(According to Hess Law)
Answer:If we dissolve NaF in water, we get the following equilibrium:
text{F}^-(aq)+text{H}_2text{O}(l) rightleftarrows text{HF}(aq)+text{OH}^-(aq)
The pH of the resulting solution can be determined if the K_b of the fluoride ion is known.
20.0 g of sodium fluoride is dissolve in enough water to make 500.0 mL of solution. Calculate the pH of the solution. The K_b of the fluoride ion is 1.4 × 10 −11 .
Step 1: List the known values and plan the problem.
Known
mass NaF = 20.0 g
molar mass NaF = 41.99 g/mol
volume solution = 0.500 L
K_b of F – = 1.4 × 10 −11
Unknown
pH of solution = ?
The molarity of the F − solution can be calculated from the mass, molar mass, and solution volume. Since NaF completely dissociates, the molarity of the NaF is equal to the molarity of the F − ion. An ICE Table (below) can be used to calculate the concentration of OH − produced and then the pH of the solution.
Explanation:
Answer:
Measure 2.47 mL of the stock solution (i.e 0.0405 mM) and dilute it to the 100 mL mark with water
Explanation:
To make 100 mL of 0.001 mM solution from 0.0405mM solution, we need to determine the volume of 0.0405mM solution needed. This can be obtained as follow:
Molarity of stock (M₁) = 0.0405 mM
Volume of diluted (V₂) = 100 mL
Molarity of diluted solution (M₂) = 0.001 mM
Volume of stock solution needed (V₁) =?
M₁V₁ = M₂V₂
0.0405 × V₁ = 0.001 × 100
0.0405 × V₁ = 0.1
Divide both side by 0.0405
V₁ = 0.1 / 0.0405
V₁ = 2.47 mL
Therefore, to make 100 mL of 0.001 mM solution from 0.0405mM solution, measure 2.47 mL of the stock solution (i.e 0.0405 mM) and dilute it to the 100 mL mark with water.
Current is the rate at which electric charge flows past a point in a circuit. In other words, current is the rate of flow of electric charge. Voltage, also called electromotive force, is the potential difference in charge between two points in an electrical field. ... Current is the effect (voltage being the cause).
