How many underwater volcanoes erupt every year??? HELP

Problem PageQuestion A chemist makes of magnesium fluoride working solution by adding distilled water to of a stock solution of

igomit [66]

Answer:

5.37 × 10⁻⁴ mol/L

Explanation:

A chemist makes 660. mL of magnesium fluoride working solution by adding distilled water to 230. mL of a 0.00154 mol/L stock solution of magnesium fluoride in water. Calculate the concentration of the chemist's working solution. Round your answer to 3 significant digits.

Step 1: Given data

Initial concentration (C₁): 0.00154 mol/L

Initial volume (V₁): 230. mL

Final concentration (C₂): ?

Final volume (V₂): 660. mL

Step 2: Calculate the concentration of the final solution

We want to prepare a dilute solution from a concentrated one. We can calculate the concentration of the final solution using the dilution rule.

C₁ × V₁ = C₂ × V₂

C₂ = C₁ × V₁ / V₂

C₂ = 0.00154 mol/L × 230. mL / 660. mL = 5.37 × 10⁻⁴ mol/L

5 0

2 years ago

When the concentration of A in the reaction A ..... B was changed from 1.20 M to 0.60 M, the half-life increased from 2.0 min to

Reika [66]

Answer:

2

$0.4167\ \text{M}^{-1}\text{min}^{-1}$

Explanation:

Half-life

${t_{1/2}}A=2\ \text{min}$

${t_{1/2}}B=4\ \text{min}$

Concentration

${[A]_0}_A=1.2\ \text{M}$

${[A]_0}_B=0.6\ \text{M}$

We have the relation

$t_{1/2}\propto \dfrac{1}{[A]_0^{n-1}}$

So

$\dfrac{{t_{1/2}}_A}{{t_{1/2}}_B}=\left(\dfrac{{[A]_0}_B}{{[A]_0}_A}\right)^{n-1}\\\Rightarrow \dfrac{2}{4}=\left(\dfrac{0.6}{1.2}\right)^{n-1}\\\Rightarrow \dfrac{1}{2}=\left(\dfrac{1}{2}\right)^{n-1}$

Comparing the exponents we get

$1=n-1\\\Rightarrow n=2$

The order of the reaction is 2.

$t_{1/2}=\dfrac{1}{k[A]_0^{n-1}}\\\Rightarrow k=\dfrac{1}{t_{1/2}[A]_0^{n-1}}\\\Rightarrow k=\dfrac{1}{2\times 1.2^{2-1}}\\\Rightarrow k=0.4167\ \text{M}^{-1}\text{min}^{-1}$

The rate constant is $0.4167\ \text{M}^{-1}\text{min}^{-1}$

3 0

2 years ago

Please help me I would really appreciate it

denis-greek [22]

The number of students is your independent variable

6 0

2 years ago

The boiling point of bromine is 59 °C. Which of the following best predicts the boiling point of iodine monochloride, a polar co

soldier1979 [14.2K]

Answer:

Higher than 59 °C because dipole-dipole interactions in iodine monochloride are stronger than dispersion forces in bromine.

Explanation:

I just took the test and i got it right

6 0

2 years ago

Read 2 more answers

Calculate the amount of energy required to melt 500 g of ice at 0oc. (δhfus=5.96 kj/mole; δhfus is the energy required to melt i

marta [7]

When you want to melt an ice, you only need the latent energy of fusion, δhfus. We use the given value, then multiply this with the given amount to determine the amount of energy. Since the energy is per mole basis, use the molar mass of ice which is 18 g/mol. The solution is as follows:

ΔH = 5.96 kJ/mol * 1 mol/18 g * 500 g
ΔH = 165.56 kJ

3 0

2 years ago