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3 years ago

Given 40 grams of magnesium. How many mole is this

1 answer:

3 0

To determine the moles in 40 grams of magnesium, we need the atomic weight. This can easily be found on a periodic table. For this problem, let's use 24.305 grams/mole.

We are going to set up an equation to determine this problem. In this equation, we want all our units to cancel out except for 'moles.'

$\frac{40 g Mg}{1} x\frac{1 mole Mg}{24.305 g Mg}$

In this, we can see that the unit 'grams' will cancel out to leave us with moles.

In solving the equation, we determine that there are approximately 1.65 moles of Magnesium.

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How are genes and alleles related

Montano1993 [528]

Alleles are inside a gene and genes are made up by alleles. Also, a gene is DNA, so the allele is like piece of DNA inside a gene.

Hope this helps:)

7 0

3 years ago

Calculate the activity coefficients for the following conditions:

uysha [10]

Answer:

For a: The activity coefficient of copper ions is 0.676

For b: The activity coefficient of potassium ions is 0.851

For c: The activity coefficient of potassium ions is 0.794

Explanation:

To calculate the activity coefficient of an ion, we use the equation given by Debye and Huckel, which is:

$-\log\gamma_i=\frac{0.51\times Z_i^2\times \sqrt{\mu}}{1+(3.3\times \alpha _i\times \sqrt{\mu})}$ ........(1)

where,

$\gamma_i$ = activity coefficient of ion

$Z_i$ = charge of the ion

$\mu$ = ionic strength of solution

$\alpha _i$ = diameter of the ion in nm

To calculate the ionic strength, we use the equation:

$\mu=\frac{1}{2}\sum_{i=1}^n(C_iZ_i^2)$ ......(2)

where,

$C_i$ = concentration of i-th ions

$Z_i$ = charge of i-th ions

For a:

We are given:

0.01 M NaCl solution:

Calculating the ionic strength by using equation 2:

$C_{Na^+}=0.01M\\Z_{Na^+}=+1\\C_{Cl^-}=0.01M\\Z_{Cl^-}=-1$

Putting values in equation 2, we get:

$\mu=\frac{1}{2}[(0.01\times (+1)^2)+(0.01\times (-1)^2)]\\\\\mu=0.01M$

Now, calculating the activity coefficient of $Cu^{2+}$ ion in the solution by using equation 1:

$Z_{Cu^{2+}}=2+\\\alpha_{Cu^{2+}}=0.6\text{ (known)}\\\mu=0.01M$

Putting values in equation 1, we get:

$-\log\gamma_{Cu^{2+}}=\frac{0.51\times (+2)^2\times \sqrt{0.01}}{1+(3.3\times 0.6\times \sqrt{0.01})}\\\\-\log\gamma_{Cu^{2+}}=0.17\\\\\gamma_{Cu^{2+}}=10^{-0.17}\\\\\gamma_{Cu^{2+}}=0.676$

Hence, the activity coefficient of copper ions is 0.676

For b:

We are given:

0.025 M HCl solution:

Calculating the ionic strength by using equation 2:

$C_{H^+}=0.025M\\Z_{H^+}=+1\\C_{Cl^-}=0.025M\\Z_{Cl^-}=-1$

Putting values in equation 2, we get:

$\mu=\frac{1}{2}[(0.025\times (+1)^2)+(0.025\times (-1)^2)]\\\\\mu=0.025M$

Now, calculating the activity coefficient of $K^{+}$ ion in the solution by using equation 1:

$Z_{K^{+}}=+1\\\alpha_{K^{+}}=0.3\text{ (known)}\\\mu=0.025M$

Putting values in equation 1, we get:

$-\log\gamma_{K^{+}}=\frac{0.51\times (+1)^2\times \sqrt{0.025}}{1+(3.3\times 0.3\times \sqrt{0.025})}\\\\-\log\gamma_{K^{+}}=0.070\\\\\gamma_{K^{+}}=10^{-0.070}\\\\\gamma_{K^{+}}=0.851$

Hence, the activity coefficient of potassium ions is 0.851

For c:

We are given:

0.02 M $K_2SO_4$ solution:

Calculating the ionic strength by using equation 2:

$C_{K^+}=(2\times 0.02)=0.04M\\Z_{K^+}=+1\\C_{SO_4^{2-}}=0.02M\\Z_{SO_4^{2-}}=-2$

Putting values in equation 2, we get:

$\mu=\frac{1}{2}[(0.04\times (+1)^2)+(0.02\times (-2)^2)]\\\\\mu=0.06M$

Now, calculating the activity coefficient of $K^{+}$ ion in the solution by using equation 1:

$Z_{K^{+}}=+1\\\alpha_{K^{+}}=0.3\text{ (known)}\\\mu=0.06M$

Putting values in equation 1, we get:

$-\log\gamma_{K^{+}}=\frac{0.51\times (+1)^2\times \sqrt{0.06}}{1+(3.3\times 0.3\times \sqrt{0.06})}\\\\-\log\gamma_{K^{+}}=0.1\\\\\gamma_{K^{+}}=10^{-0.1}\\\\\gamma_{K^{+}}=0.794$

Hence, the activity coefficient of potassium ions is 0.794

6 0

3 years ago

Someone pls help me I will make you brain

Katena32 [7]

Answer:

it is actually b because i did this i picked b and got it right

Explanation:

4 0

3 years ago

Use the periodic table to identify each of the following bonds as polar or nonpolar.

Molodets [167]

Answer:

Polar

Step-by-step explanation:

Electronegativity increases from left to right in the Periodic Table.

Cl is further right than C (both tinted pink) in the portion of the Periodic Table below.

Cl is more electronegative than C, so the Cl has a partial negative charge and the C has a partial positive charge.

The C-Cl bond is polar.

5 0

3 years ago

A naoh (aq) stock solution was created by dissolving 3.88 g naoh in water to create a 100.00 ml solution. what is the concentrat

Bess [88]

0.0381g/mL will be concentration of this solution

The ratio of a solute—a substance that dissolves—to a solvent—a substance that does not dissolve—determines the concentration of a solution in chemistry. C = m/V, where C is the concentration, m is the mass of the solute dissolved, and V is the overall volume of the solution, is the accepted formula.

How to reach the solution?

First find for the density of NaOh which is 2.13 g/cm3

3.88 ÷ 2.13 = 1.82mL

100mL + 1.82mL = 101.82mL

3.88 ÷ 101.82mL = 0.0381g/mL

More about NaOh:

The extremely adaptable chemical sodium hydroxide (NaOH), sometimes referred to as caustic soda or lye, is employed in a range of manufacturing processes. A byproduct of the manufacturing of chlorine is sodium hydroxide. Numerous items that are used on a daily basis, including paper, metal, drain and oven cleansers for industry, soap, and detergents, are made with sodium hydroxide.

Learn more about Naoh here:

brainly.com/question/3366922

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5 0

1 year ago