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3 years ago

HELP HELP IM FAILING PLZ HELP ME

Chemistry

2 answers:

Dvinal [7]3 years ago

7 0

Answer:

236 g/mol

Explanation:

RoseWind [281]3 years ago

6 0

Answer:

236 g/mol

Explanation:

This question is asking to calculate the molar mass/formula mass of calcium nitrate tetrahydrate with the chemical formula: Ca(NO3)2 · 4H20. This is done as follows:

Atomic mass of the constituent elements are as follows:

Ca = 40

N = 14

O = 16

H = 1

Hence, in Ca(NO3)2 · 4H20.

= 40 + {14 + 16(3)}2 + 4 {1(2) + 16}

= 40 + {14 + 48}2 + 4{2 + 16}

= 40 + {62}2 + 4{18}

= 40 + 124 + 72

= 236

Hence, the molar mass of Ca(NO3)2 · 4H20 is 236g/mol.

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The powder mixture (Cu, Al and Fe) = 10g was oxidized from sufficient chloride acid. 1) What are the possible reactions to the p

Mandarinka [93]

Answer:

1) 2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

Explanation:

1) Possible reactions

2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Mass of each metal

a) Mass of Cu

The waste was the unreacted copper.

Mass of Cu = 2.5 g

b) Masses of Al and Fe

We have two relations :

Mass of Al + mass of Fe = 10 g - 2.5 g = 7.5 g

H₂ from Al + H₂ from Fe = 6.38 L at NTP

i) Calculate the moles of H₂

NTP is 20 °C and 1 atm.

$\begin{array}{rcl}pV & = & n RT\\\text{1 atm} \times \text{6.38 L} & = & n \times 0.08206 \text{ L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1} \times \text{293.15 K}\\6.38 & = & 24.06n \text{ mol}^{-1} \\n & = & \dfrac{6.38}{24.06 \text{ mol}^{-1} }\\\\ & = & \text{0.2652 mol}\\\end{array}$

(ii) Solve the relationship

Let x = mass of Al. Then

7.5 - x = mass of Fe

Moles of Al = x/27

Moles of Fe = (7.5 - x)/56

Moles of H₂ from Al = (3/2) × Moles of Al = (3/2) × (x/27) = x /18

Moles of H₂ from Fe = (1/1) × Moles of Fe = (7.5 - x)/56

∴ x/18 + (7.5 - x)/56 = 0.2652

56x + 18(7.5 - x) = 267.3

56x + 135 - 18x = 267.3

38x = 132.3

x = 3.5 g

Mass of Al = 3.5 g

Mass of Fe = 7.5 g - 3.5 g = 4.0 g

The masses of the metals are Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

4 0

4 years ago

The element in Group 14 Period 4 has how many neutrons and is it a metal, nonmetal, metalloid or noble gas.

monitta

Number of neutrons=41, and it is metalloid

<h3>Further explanation</h3>

Group 14⇒valence electron = 4(ns²np²)

Period 4⇒n=4

So electron configuration of the element :

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p² = 32 electron=atomic number

The element with atomic number 32, which is in period 4 and group 14 is Ge-Germanium

There are seven elements that can be classified as metalloids, namely boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), and polonium (Po).

While the mass number: 73

So the number of neutrons = mass number-atomic number

$\tt 73-32=41$

8 0

3 years ago

What is the molariity of a 50.0 mL aqueous solution containing 10.0 grams of hydrogen peroxide, H2O2?

daser333 [38]

Answer:

6 mol/L

Explanation:

You should know or have the equation to solve for Molarity which is;

M = n/v (M: Molarity) (n: moles of solute) (v: Liters of solute)

You can start off differently but I would start by converting the mL to L. This is your "v" value.

50.0 mL/ 1000 mL = <em>0.05 L</em>

Now, you have to convert grams to moles in order to solve for molarity (M).

1.) On the periodic table find the molecular weights of H and O.

H= 1.01 g/mol O= 16.00 g/mol

2.) Multiply them and then add them together to have their combined molecular weights. (You have to multiply by 2 because of their equation; H2O2).

2(1.01) + 2(16.00)= 34.02 g/mol

3.) Now, you're going to use the "picket fence method" or whichever your teacher taught you to convert from grams to moles. This will be your "n" value. (I cannot show it on here without it looking weird, so my sincere apologies.)

10.0 g/ 34.02 g = <em>0.2939 mol</em>

<em />

4.)You are now going to plug in your answers into the equation for Molarity.

M= 0.2939 mol / 0.05 L = <em>5.878 mol/L</em>

5.) I am sure your professor might be a stickler so for sig figs sake when you multiply or divide use the smallest amount of sig figs you see which is 1. Round 5.878 to 6 mol/L

Sorry this explanation is very long let me know if you need a better more written out explanation.

4 0

4 years ago

Fossil fuels are considered to be __________ resources because they are consumed ___________ than they form.

mixas84 [53]

Fossil fuels are formed by the deposition of organic matter. It is a nonrenewable resource as they deplete faster as they are produced. Thus, option B is correct.

<h3>What is non-renewable resources?</h3><h3 />

A non-renewable resource is exhaustible and takes a longer time to get produced as they include the accumulation of organic matter over thousands of years.

Fossil fuels take a very long time to get replenished and have a slower rate of formation as compared to consumption. It includes petrol, coal, diesel, natural gases, etc.

Therefore, option B. nonrenewable and far faster are the correct blanks.

Learn more about the non-renewable resources here:

brainly.com/question/11778974

#SPJ1

8 0

2 years ago

Pls answer fast chem questions

gregori [183]

I don't recognize this problem, please make sure the input is complete.

7 0

3 years ago