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Answer:

In a molecular formula, it states the total number of atoms of each element in a molecule.

Explanation:

Answer:

C. volume

Explanation:

Answer:

D

Explanation:

Answer:

Sodium hydrogen trioxocarbonate(IV) is also known as baking soda, and has the molecular formula NaHCO3. Industrial Preparation of NaHCO3. The salt is manufactured industrially by the solvay process by saturating a wet mush of Na2CO3 obtained from the solvay process with CO2. Na2CO3(aq) + H2O(l) + CO2(g) → 2NaHCO3(s)

Explanation:

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Answer:

Explanation:

We know that

pH +pOH = 14

Given pH = 8.30

⇒ p0H = 14-8.30 = 5.70

Since, we know that

[tex]10^{-pH} = [H^{+}][/tex]

Answer:

4 moles of HCl will be required to produce 2 moles of H2.

Explanation:

A balanced chemical equation gives the stoichiometric ration of moles of reactants required to produce a certain number of moles of products. The ratio of moles of reactants to moles of products is known as the mole ratio and is constant for a given chemical reaction.

In the given balanced equation of reaction shown below:

Zn + 2HCl → ZnCl2 + H2

The mole ratio of HCl and H2 is 2:1. This means that in this reaction between Zinc metal and hydrochoric acid to produc zinc chloride and hydrogen gas, every two moles of hydrochloric acid used in the reaction will result in the production of one mole of hydrogen gas.

Therefore for two moles of H2 to be obtained from the reaction, twice the number of moles of HCl is required.

Moles of HCl required = 2 × 2 moles = 4 moles of HCl.

Answer:I’m 100% it’s the second one

Explanation:

I have done it before and missed one but not this question

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

we have

[tex]n = \frac{1.88 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 31.229235...[/tex]

We have the final answer as

Hope this helps you

Answer:

350.64g

Explanation:

So first you must know that M is mol/L

Next solve the problem using dimensional analysis

2L NaCl (3 mol/L) = 6 mol NaCl

After you got the number of moles you should look at your periodic table to find the molar mass

I see that it's 58.44g/mol

Use dimensional analysis again!

6 mol (58.44g/mol) = 350.64g

Don't forget to make me brainliest!

Answer:

Explanation:

"Oxygen fuels our living processes. It contracts our muscles, helps our cells to work, grow and regenerate, feeds our brains, calms our nerves, helps the heart to pump, cleanses the body of toxins, fights infection and boosts immunity," says Dr  Jena, Director, Institute of Emergency Medicine, Mission Hospital & Research Center , Madurai.

Lungs:

Once air enters the nose or mouth, it gets humidified and reaches the oliveoli, tiny air sacs that help to pull in oxygen and transfer it into the blood stream and also to pull out the carbon dioxide and push it out of the lungs and back up to breathe out.  destroys these oliveoli by thickening the walls so gas exchange becomes difficult.

Heart :

The left side of your heart receives oxygen-rich blood from your lungs and pumps it through your arteries to the rest of your body. The right side of your heart receives oxygen-poor blood from your veins and pumps it to your lungs, where it gets rid of the carbon dioxide and picks up oxygen. Inan increase in oxygen demand occurs because of compromised lungs and fear (that excites the body). This may lead to heart damage, especially if the arteries were already clogged.

this may help you hope so

Answer:

7. Option 2. Atom 1 and Atom 4

8. The same number of valence electron

Explanation:

7. Determination of which symbol represent an isotope.

Isotopes are atoms having the same atomic number but different mass number due to the difference in the neutron number.

From the question given above, the following were obtained:

Z => atomic number

A => mass number

Atom >>> Isotope >>>>> Z >>>> A

1 >>>>>>> ¹⁷₇E >>>>>>>> 7 >>>> 17

2 >>>>>>> ¹⁷₈E >>>>>>> 8 >>>> 17

3 >>>>>>> ¹⁸₆E >>>>>>> 6 >>>> 18

4 >>>>>>> ¹⁸₇E >>>>>>> 7 >>>> 18

From the table above, only atom 1 and 4 has the same atomic number. Hence, atom 1 and atom 4 are isotopes.

8. To know the correct answer to the question, we shall write the electronic configuration of magnesium and calcium. This can be obtained as follow:

Mg (12) => 1s² 2s²2p⁶ 3s²

Valence electron => 2

Ca (20) => 1s² 2s²2p⁶ 3s²3p⁶ 4s²

Valence electron => 2

We can see that magnesium and calcium both have the same valence electron. Hence, they will have similar chemical properties.

The required molecule is :

=》option B.) C2H4O2

it has 2 carbon atoms, 4 hydrogen atoms which it twice the number of carbon atoms and 2 oxygen atoms same as carbon.

Answer:

88g of Sr(NO3)2 are present

Explanation:

To solve this question we must, as first, find the moles of oxygen. Based on the chemical formula of strontium nitrate, there are 6 atoms of oxygen per mole of strontium nitrate. Thus, we can find the moles of strontium nitrate and its mass as follows:

Moles Oxygen:

40g * (1mol / 16g) = 2.5 moles Oxygen

Moles Strontium nitrate:

2.5 moles Oxygen * (1mol Sr(NO3)2 / 6mol O) = 0.4167 moles Sr(NO3)2

Mass (Molar mass Sr(NO3)2: 211.63g/mol)

0.4167 moles Sr(NO3)2 * (211.63g / mol) =

Answer:

limited

Explanation:

have a good day :)

Answer:

the answer is b edg 2021

Explanation:

it just is

Answer:

2Li + 2H2O → 2LiOH + H2

Explanation:

Lithium + Water = Lithium Hydroxide + Dihydrogen

Answer:

It would take 13 minutes.

Explanation:

The temperature decreases at a linear rate, meaning that we can describe the process by using the following formula:

Where T₂ is the final temperature, T₀ is the initial temperature; and t is the elapsed time in minutes.

We input the data given by the problem:

And solve for t:

Answer:

its B

Explanation:

I took the test and its that passage way thing. (tell me if this works for you! it will but just wanna make sure!)

Explanation:

Explanation:

Given the molecular weights:

M

r

N

a

O

H

=

40

g

m

o

l

M

r

N

a

2

S

O

4

=

142

g

m

o

l

The analogy of the moles will be held constant:

n

N

a

O

H

n

N

a

2

S

O

4

=

2

1

n

N

a

O

H

n

N

a

2

S

O

4

=

2

For each one, substitute:

n

=

m

M

r

Therefore:

n

N

a

O

H

n

N

a

2

S

O

4

=

2

m

N

a

O

H

M

r

N

a

O

H

m

N

a

2

S

O

4

M

r

N

a

2

S

O

4

=

2

200

40

x

142

=

2

200

⋅

142

40

x

=

2

200

⋅

142

=

2

⋅

40

x

x

=

200

⋅

142

2

⋅

40

=

100

⋅

142

40

=

10

⋅

142

4

=

1420

4

=

=

710

2

=

355

g

r

a

m

s

(or just use a calculator

Answer:

b

Explanation:

i took the quiz

Answer:

D. The energy level of the electron.

Explanation:

There are four quantum numbers which are used to describe the movement and paths or positon of each electron within an atom. Quantum numbers can be used to determine the electronic configuration of atoms and the most likely location of the atom's electrons. Quantum numbers are also used in determining other characteristics of atoms, such as ionization energy and the atomic radius.

The four quantum numbers are namely, principal, azimuthal, magnetic and spin quantum numbers.

Principal quantum numbers are denoted by the symbol ‘n’. They describe the principal electron shell or energy level the atom.The value of the principal quantum number are positive integer values that is equal to or greater than one. The value n = 1 represents the innermost electron shell of an atom, which corresponds to the lowest energy state of an electron. The larger the values of 'n' the greater the energy level and the farther the electron is from the nucleus.

Answer: B

Explanation:

1.5 :D

Answer:

1) 90.0 mL

2) 11.25 M

3) 0.477 M

4) 144 mL

Explanation:

The main formula that will be used for all these calculations is:

                                                     C₁V₁ = C₂V₂

C stands for concentration and V stands for volume and the subscripts 1 and 2 indicate an initial concentration or volume and a final concentration or volume.

For each problem, it's best to start by figuring out what you have and what you need to find. Figure out if you're looking for an initial value or a final value.

1) We need to find the initial volume. So, take what values you have and plug them in and then solve for whatever variable:

5.00 M · V₁ = 500.0mL · 0.900 M                        - divide by 5.00

C₁ = 90.0 mL

2) This time we're finding the initial concentration:

20.0mL · C₁ = 150.0mL · 1.50 M                          - divide by 20.0mL

C₂ = 11.25 M

3) Now we're finding the final concentration:

12.00mL · 3.50 M = 88.0mL · C₂                         - divide by 88.0mL

C₂ = 0.477 M

4) Finally, we're looking for the final volume:

9.0mL · 8.0 M = 0.50 M · V₂                                - divide by 0.50 M

V₂ = 144mL

Answer:

79.89%

Explanation:

Copper has a molar mass of 63.55

Oxygen has a molar mass of 16.00

If you add these you get 79.55

To get the mass percent of copper divide copper by the whole. 63.55/79.55*100= 79.89%

Answer:

19ml

Explanation:

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