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3 years ago

Which substance can not be broken down by a chemical change?

1 answer:

8 0

(4) Zirconium
This element is often used in the chemical production field, and as implants due to its high chemical resistance and stability.

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You wish to prepare 250.0250.0 mL of a 400.0400.0 ppm w/v Fe2+Fe2+ ( MW=55.845 g/molMW=55.845 g/mol ) solution. How many grams o

tresset_1 [31]

Answer:

You need 0.702g of ferrous ammonium sulfate hexahydrate to prepare the desired solution.

Explanation:

First, you want to prepare 250.0mL of a 400.0ppm of Fe²⁺ (That is mg/L, w/v):

0.250L * (400mg / L) = 100mg Fe²⁺ = 0.1g Fe²⁺

Molar mass of Fe is 55.845g. moles are:

0.1g Fe²⁺ * (1mol / 55.845g) =

<h3>1.79x10⁻³ moles Fe²⁺</h3>

The Fe²⁺ comes from ferrous ammonium sulfate hexahydrate, as 1 mole of this salt contains 1 mole of Fe²⁺, moles of the salt you need are:

1.79x10⁻³ moles Fe(NH₄)₂(SO₄)₂.6H₂O.

To convert these moles to grams you must use molar weight, MW, thus:

1.79x10⁻³ moles Fe(NH₄)₂(SO₄)₂.6H₂O * (392.14g / 1mol) =

<h3>You need 0.702g of ferrous ammonium sulfate hexahydrate to prepare the desired solution.</h3>

3 0

3 years ago

What is the volume in liters of 5.25 moles of He gas?

serious [3.7K]

Answer:

$\boxed {\boxed {\sf 117.6 \ L \ He}}$

Explanation:

Regardless of the type of gas, 1 mole at standard temperature and pressure (STP) occupies a volume of 22.4 liters. In this case the gas is helium (He).

We can set up a ratio.

$\frac { 22.4 \ L \ He}{ 1 \ mol \ He}$

Multiply by the given number of moles.

$5.25 \ mol \ He *\frac { 22.4 \ L \ He}{ 1 \ mol \ He}$

The moles of helium will cancel.

$5.25 *\frac { 22.4 \ L \ He}{ 1 }$

$5.25 * { 22.4 \ L \ He}$

Multiply.

$117.6 \ L \ He$

5.25 moles of helium gas at STP is 117.6 liters of helium.

5 0

3 years ago

Rain that containing excess of acid is called

Oxana [17]

Answer:

The rain containing excess of acid I called acid rain

4 0

2 years ago

Read 2 more answers

How many atoms are in 12 moles of I. Check your significant figures.

ELEN [110]

Explanation:

7.2×1024 moleas

please mark as brilliant

5 0

2 years ago

This is the process that cells reproduce and replace old or damaged cells.

Vedmedyk [2.9K]

Answer:

mitosis

Explanation:

because ur a cumt who doesn't know the answer

8 0

3 years ago