Heat energy is useful to us in all the following ways except:

Heat energy can be harnessed to warm homes.
Heat is converted to mechanical energy in engines to do work.
Heat energy can be used to melt materials and change their shape to create useful objects.
Heat energy is transferred to cooler objects to reduce the temperature of those objects.

Answer:

1.67 M

Explanation:

The following data were obtained from the question:

Initial volume (V1) of solution = 250 mL

Initial Molarity (M1) of solution = 0.5 M

Final volume (V2) of solution = 75 mL

Final Molarity (M2) of solution =?

Thus, we can obtain the final molarity of the solution by using the following formula:

M1V1 = M2V2

0.5 × 250 = M2 × 75

125 = M2 × 75

Divide both side by 75

M2 = 125 /75

M2 = 1.67 M

Thus, the new Molarity of the solution is 1.67 M.

Mass of sodium carbonate = 7.022 g

Reaction

Na₂CO₃ + 2HNO₃ ⇒ 2NaNO₃ + H₂O + CO₂

mol of HNO₃ (MW=63,01 g/mol):

[tex]\tt mol=\dfrac{8.35}{63.01}=0.1325[/tex]

mol Na₂CO₃

[tex]\tt \dfrac{1}{2}\times 0.1325=0.06625[/tex]

mass Na₂CO₃(MW = 105,9888 g/mol) :

[tex]\tt 0.06625\times 105,9888 g/mol=7.022~g[/tex]

The mass of sodium carbonate that is required for complete reaction with 8.35 grams of nitric acid is equal to 7.02 grams.

Given the following data:

Scientific data:

To determine the mass of sodium carbonate that is required for complete reaction with 8.35 grams of nitric acid:

First of all, we would write the properly balanced chemical equation for this chemical reaction:

                        [tex]Na_2CO_3 + 2HNO_3 \rightarrow 2NaNO_3 + H_2O + CO_2[/tex]

Next, we would find the number of moles of nitric acid ([tex]HNO_3[/tex]) required:

[tex]Number\;of\;moles = \frac{Mass}{molar\;mass}\\\\Number\;of\;moles = \frac{8.35}{63 }[/tex]

Number of moles = 0.1325 moles.

By stoichiometry:

2 moles of [tex]HNO_3[/tex] = 1 mole of [tex]Na_2CO_3[/tex]

0.1325 moles of [tex]HNO_3[/tex] = X mole of [tex]Na_2CO_3[/tex]

Cross-multiplying, we have:

[tex]2X=0.1325\\\\X=\frac{0.1325}{2}[/tex]

X = 0.0663 moles

Now, we can determine the mass of sodium carbonate that is required:

[tex]Mass = Number\;of\;moles \times molar\;mass\\\\Mass = 0.0663 \times 106[/tex]

Mass of [tex]HNO_3[/tex] = 7.02 grams

Read more: https://brainly.com/question/16906167

Answer:

A

Explanation:

Answer:

its the first one because all together it has to have ten square things

Answer:

C

Explanation:

The stomach digests the food (Digestive System) are the nerves and they send the protein etc.

Answer:

Global warming is causing global mean sea level to rise in two ways. First, glaciers and ice sheets worldwide are melting and adding water to the ocean. ... A third, much smaller contributor to sea level rise is a decline in the amount of liquid water on land—aquifers, lakes and reservoirs, rivers, soil moisture.

Explanation:

Answer:

It has caused sea levels to rise and caused glaciers to melt.

Explanation:

Because glaciers and ice caps are melting rapidly and they store about 1.7% all of Earth's water, causing sea levels to rise.

A. Breaking a Cl-Br bond

Answer:

Chlorine has higher Electron Affinity as compared to Bromine

Explanation:

Electron affinity is defined as the Potential energy change of the atom when an electron is added to a neutral gaseous atom. Therefore, more the Negative electron affinity, more favorable will be the electron addition process.

The electron affinity of Chlorine is -349kJmol^-1

The electron affinity of Bromine is -324.6KJmol^-1

This clearly shows that Chlorine is a much better Atom to be bonded with, That is the reason why in the reaction is not feasible.

[tex]Br2(aq) + 2NaCl(aq)[/tex] →[tex]Cl2(aq) + 2NaBr(aq)[/tex]

Therefore, Chlorine has higher electron Affinity as compared to Bromine and that what makes it a much better atom to be bonded with Na. So the above reaction is not possible.

The number of moles : 6.2 x 10¹¹

The mole is the number of particles contained in a substance

1 mole = 6.02.10²³  particles

[tex]\tt N=n\times No[/tex]

N = number of particles

n = moles

No = Avagadro's number : 6.02.10²³

3.73 x 10³⁵ atoms of S

the number of moles :

[tex]\tt \dfrac{N}{No}=\dfrac{3.73\times 10^{35}}{6.02\times 10^{23}}=6.2\times 10^{11}[/tex]

Answer:

I think it’s chlorine (Cl)

Explanation:

I’m literally doing the same question right now

Answer:

sp hybridized orbitals

The bond angle is 180 degrees

Explanation:

Molecules are formed by overlap of atomic orbitals. Hybridization is a valence bond concept. According to this concept, atomic orbitals are mixed to obtain orbitals of appropriate energy, suitable for bonding.

The sigma bonds in CO2 are formed by sp hybridized carbon atoms. The bond angle of sp hybridized carbon atoms is 180 degrees leading to a linear shape.

Answer:

1. Si

hope this helped

If u click on all of them it gives u an A+ and doesn’t even read what u wrote. So u never really have to try hard on the writing parts just tell them u included them all

Answer:An image will not be formed.

Rays do not converge to or diverge from a common point.

/select all that apply

Explanation:

The percentage CaCl₂ : 65.14%

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

Reaction

3CaCl₂+2Na₃PO₄⇒Ca₃(PO₄)₂ + 6NaCl

mol Ca₃(PO₄)₂(MW=310.18 g/mol) :

[tex]\tt \dfrac{0.425}{310.18}=0.00137[/tex]

mol ratio CaCl₂ : Ca₃(PO₄)₂ = 3 : 1, so mol CaCl₂ :

[tex]\tt \dfrac{3}{1}\times 0.00137=0.00411[/tex]

mass CaCl₂ (MW=110.98 g/mol) :

[tex]\tt 0.00411\times 110.98=0.456~g[/tex]

The percentage CaCl₂ :

[tex]\tt \%CaCl_2~in~mixture=\dfrac{0.456}{0.7}\times 100\%=65.14\%[/tex]

2-methyl-butanamide hydrolysis with NaOH forms a carboxyllic acid, sodiun salt of 2-methyl butanoic acid and ammonia

Explanation:

Answer:

My group believes that Elisa has Staphylococcus Aureus. I think that she does have the manifestation of the colonies condition because she tested positive to clumping factor, coagulase, hemolysins and thermostable deoxyribonuclease, which are used to identify S aureus. Commercial latex agglutination tests conducted on her blood sample also tested positive to the S aureus. For further clarifications, my Group also used biotyping kits for the identification of S epidermidis for commercial confirmation.

However, the catalase test was conducted to distinguish streptococci (catalase-negative) staphylococci which are catalase positive. The test was performed by flooding an agar slant or broth culture with several drops of 3% hydrogen peroxide. Catalase-positive cultures bubble at once.

Explanation:

I have a question, is this in Edge 2020?

And anyway,

Hope this helped! :)

Answer:

a substance that can be dissolved by a solvent to create a solution

Explanation:

Answer:

the minor component in a solution dissolved in a solvent

Answer:

6.02 X 1023 atoms of oxygen.

Explanation:

One mole of atoms of oxygen has a mass of 16 g, as 16 is the atomic weight of oxygen, and contains 6.02 X 1023 atoms of oxygen.

the number of oxygen atoms an oxygen molecule has is two oxygen atoms

Answer:

The correct answer is 5.6 × 10⁻²³ M.

Explanation:

As a highly soluble salt, KBr dissolves easily in water, while Hg₂Br₂ is very less soluble in comparison to KBr.

Let the solubility of Hg₂Br₂ is S mol per liter.

Therefore,

KBr (s) (1.0 M) ⇒ K⁺ (aq) (1M) + Br⁻ (aq) (1M)

Hg₂Br₂ (s) (1-S) ⇔ Hg₂⁺ (aq) (S) + 2Br⁻ (aq) (2S)

Net [Br-] = (2S + 1) M

Ksp = S (2S + 1)²

Ksp = S (4S² + 1 + 4S)

Ksp = 4S³ + S + 4S²

As the solubility is extremely less, therefore, we can ignore S² and S³. Now,

Ksp = S = 5.6 × 10⁻²³ M

Hence, the solubility of Hg₂Br₂ is 5.6 × 10⁻²³ M.

Answer:

1. 40 grams of NaCI

2. 20 grams of Barium Peroxide

Explanation:

For Question 1, there are 400 grams of NaCI. There are 10 drops.

So, we have to divide 400 by 10.

We get 40 as our result, so 40 is the answer.

There are 800 grams of barium peroxide, and there are 40 drops.

So, we divide 800 by 40.

We have the answer as 20.

Our final answers are going to be listed below:

Hope this helps you!

*Make proportions to solve. Find the rate from the question 1.

Question 1 is 40.

There are 400 grams of NaCI. There are 10 drops.

Divide 400 by 10.

400 / 10 = 40

40 is the answer.

Now all we do is repeat the same process for question 2.

Question 2 is 20.

There are 800 grams of barium peroxide, and there are 40 drops.

Divide 800 by 40.

800 / 40 = 20

Answer = 20.

Answer:

D. A reaction or change in a substance that results in a different substance

Explanation:

Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.

Atoms form molecules. A molecule is a chemical structure consisting of at least two atoms held together by one or more chemical bonds. ... All living things are made of cells; the cell itself is the smallest fundamental unit of structure and function in living organisms.

Answer:

Explanation: Atoms form molecules. A molecule is a chemical structure consisting of at least two atoms held together by one or more chemical bonds. ... All living things are made of cells; the cell itself is the smallest fundamental unit of structure and function in living organisms.

Answer:

a =  4 ms⁻²

Explanation:

Given data:

Mass of person = 60 Kg

Mass of sled = 15 kg

Applied force = 300 N

Acceleration = ?

Solution:

Formula:

F = ma

F = force

m = mass

a = acceleration

now we will put the values in formula.

300 N = (60 Kg+ 15 kg) × a

300 N = 75 Kg  × a

a = 300 N/ 75 Kg

N = kgm/s²

a =  4 ms⁻²

Answer:

answers

1. 3

2. Symbol

3. I cant see it

4.Chemical Equation

Explanation:

O3 means 3 atoms in oxygen

symbol because elements need symbols

Answer:

4.C, 5.D, 6.A, 7.A ,and is 8.A

Answer:

2Fe + 3Cl=2FeCl3 therefore the coefficent for Fe is 2.

Explanation:

Answer:

The correct answer is 0.089 g/L ≅ 0.09 g/L

Explanation:

Density is defined as: mass/volume.

From the problem we have:

number of moles = n = 3 mol

volume = V = 67.20 L

We have to calculate the mass. For this, we need the molar mass (MM) of the gas. That is easily calculated from the molar mass of the element hydrogen (H), as we know that hydrogen gas has the molecular formula H₂:

MM(H₂) = 2 x molar mass H = 2 x 1 g/mol = 2 g/mol

Now, we multiply n by MM to obtain the mass (m) of the gas:

m = n x MM(H₂) = 3 mol x 2 g/mol = 6 g

Finally, we calculate the density from the mass and volume:

density = m/V = 6 g/(67.20) = 0.089 g/L ≅ 0.09 g/L