50 POINTS Gizmos Moles Activity - chemistry can someone please help me out

Enter your answer in the provided box. The atomic masses of 63Cu (69.17 percent) and 65Cu (30.83 percent) are 62.94 and 64.93 am

dybincka [34]

Answer: The average atomic mass of copper is 63.55 amu.

Explanation:

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

For $_{29}^{63}\textrm{Cu}$ isotope:

Mass of $_{29}^{63}\textrm{Cu}$ isotope = 62.94 amu

Percentage abundance of $_{29}^{63}\textrm{Cu}$ = 69.17 %

Fractional abundance of $_{29}^{63}\textrm{Cu}$ isotope = 0.6917

For $_{29}^{65}\textrm{Cu}$ isotope:

Mass of $_{29}^{65}\textrm{Cu}$ isotope = 64.93 amu

Percentage abundance of $_{29}^{65}\textrm{Cu}$ = 30.83 %

Fractional abundance of $_{29}^{65}\textrm{Cu}$ isotope = 0.3083

Putting values in equation 1, we get:

$\text{Average atomic mass of Copper}=[(62.94\times 0.6917)+(64.93\times 0.3083)]\\\\\text{Average atomic mass of copper}=63.55amu$

Hence, the average atomic mass of copper is 63.55 amu.

4 0

3 years ago

Calculate the number of sulfate ions in 41.65 g of aluminum sulfate.

scoray [572]

The number of sulfate ions : 2.2 x 10²³

<h3>Further explanation</h3>

Reaction

Al₂(SO₄)₃⇒2Al³⁺+3SO₄²⁻

mol Al₂(SO₄)₃(MW=342,15 g/mol) :

$\tt \dfrac{41.65}{342.15}=0.122$

mol of sulfate ions (SO₄²⁻)

$\tt 3\times 0.122=0.366$

1 mol = 6.02 x 10²³ particles (ions, molecules, atoms), so for 0.366 mol :

$\tt 0.366\times 6.02\times 10^{23}=2.20\times 10^{23}$

8 0

3 years ago

What would the total surface area be if our large cube were divided into 8000 cubes with each side having a length of 1 cm?

ANEK [815]

Answer:

48 000 cm^2

Explanation:

8000 1cm cubes

each 1 cm cube side is 1 cm^2 and there are six sides to the cube , so each cube has 6 cm^2 surface area

and there are 8000 of them 8000 * 6 cm^2 = 48 000 cm^2

7 0

3 years ago

What is the representative particle for silicon

valentina_108 [34]

The representative particle for silicon is atom of silicon.
Representative particles can be atoms, molecules, formula units or ions. Representative particles depend on the nature of the substance. Silicon is chemical element made of atoms.
For sodium chloride (NaCl) for example, representative particles are ions.

7 0

3 years ago

When 4.41g of phosphoric acid (H3PO4) react with 9.25g of barium hydroxide, water and insoluble barium phosphate form. [T/I-7] a

AnnZ [28]

Answer:

2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + 6 H₂O(l)

Explanation:

Let's consider the unbalanced equation that occurs when phosphoric acid reacts with barium hydroxide to form water and barium phosphate. This is a neutralization reaction.

H₃PO₄(aq) + Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + H₂O(l)

We will balance it using the trial and error method.

First, we will balance Ba atoms by multiplying Ba(OH)₂ by 3 and P atoms by multiplying H₃PO₄ by 2.

2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + H₂O(l)

Finally, we will get the balanced equation by multiplying H₂O by 6.

2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + 6 H₂O(l)

3 0

3 years ago

50 POINTSGizmos Moles Activity - chemistrycan someone please help me out