All categories

3 years ago

How many moles of al does 13.49 g of al represent?

Chemistry

1 answer:

Harlamova29_29 [7]3 years ago

7 0

Use equation
number of moles= sample mass/molar mass

You might be interested in

Some elements are liquids or gases. True False

gregori [183]

The answer to this ? is true

4 0

3 years ago

If the [H3O+] of a solution is 1x 10-8 mol/L the [OH-] is

Studentka2010 [4]

Answer:

(H30+)= 1x10^-6 M

Explanation:

Both pH and pOH have a relationship to belonging to the same aqueous solution: the expression of the Kwater (ionic product of the water Kw) is used:

1x 10-8 mol/L equals to1x10-8 M

(H3O+) x (OH-) = 1x10^-14

(H30+)x 1x 10^-8 =1x10^-14

(H30+)= 1x10^-14/1x 10^-8

(H30+)= 1x10^-6 M

6 0

3 years ago

The half life for the decay of carbon- is years. Suppose the activity due to the radioactive decay of the carbon- in a tiny samp

EleoNora [17]

The question is incomplete. The complete question is:

The half-life for the decay of carbon-14 is 5.73x10^3 years. Suppose the activity due to the radioactive decay of the carbon-14 in a tiny sample of an artifact made of woodfrom an archeological dig is measured to be 2.8x10^3 Bq. The activity in a similiar-sized sample of fresh wood is measured to be 3.0x10^3 Bq. Calculate the age of the artifact. Round your answer to 2 significant digits.

Answer:

570 years

Explanation:

The activity of the fresh sample is taken as the initial activity of the wood sample while the activity measured at a time t is the present activity of the wood artifact. The time taken for the wood to attain its current activity can be calculated from the formula shown in the image attached. The activity at a time t must always be less than the activity of a fresh wood sample. Detailed solution is found in the image attached.

6 0

3 years ago

Determine the mass in grams of 3.75 x 10^21 atoms of zinc. (the mass of one mole of zinc is 65.39 g)

Nastasia [14]

Answer: The mass in $3.75 \times 10^{21}$ atoms of zinc is 0.405 g.

Explanation:

Given: Atoms of zinc = $3.75 \times 10^{21}$

It is known that 1 mole of every substance contains $6.022 \times 10^{23}$ atoms. So, the number of moles in given number of atoms is as follows.

$Moles = \frac{3.75 \times 10^{21}}{6.022 \times 10^{23}}\\= 0.622 \times 10^{-2}\\= 0.0062 mol$

As moles is the mass of a substance divided by its molar mass. So, mass of zinc (molar mass = 65.39 g/mol) is calculated as follows.

$Moles = \frac{mass}{molar mass}\\0.0062 mol = \frac{mass}{65.39 g}\\mass = 0.405 g$

Thus, we can conclude that the mass in $3.75 \times 10^{21}$ atoms of zinc is 0.405 g.

6 0

3 years ago

Which one of the following statements is correct?

adell [148]

Answer:

Tissues form organs, and organs form systems. Hope this helped!

Explanation:

7 0

3 years ago