12-How many elements are in the mixture pictured below?
A-7
O B-4
C-3
D-2

Answer: The empirical formula of X  is [tex]Cr_2O_3[/tex]

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of Cr = 68.4 g

Mass of O = 31.5 g

Step 1 : convert given masses into moles.

Moles of Cr =[tex]\frac{\text{ given mass of Cr}}{\text{ molar mass of Cr}}= \frac{68.4g}{52g/mole}=1.31moles[/tex]

Moles of O =[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{31.5g}{16g/mole}=1.97moles[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Cr = [tex]\frac{1.31}{1.31}=1[/tex]

For O = [tex]\frac{1.97}{1.31}=1.5[/tex]

The simple whole number ratio of Cr : O= 2: 3

Hence the empirical formula is [tex]Cr_2O_3[/tex]

Answer:

Option B. Plutonium-243

Explanation:

To know the the correct answer to the question, we shall write the balanced equation for the reaction showing curium-247 (²⁴⁷Cm) emitting alpha particle. This is illustrated below:

²⁴⁷₉₆Cm —> ᵐₙX + ⁴₂He

Next, we shall determine m, n and X. This can be obtained as follow:

247 = m + 4

Collect like terms

247 – 4 = m

243 = m

Thus, m is 243

96 = n + 2

Collect like terms

96 – 2 = n

94 = n

Thus, n is 94

m = 243

n = 94

ᵐₙX => ²⁴³₉₄X => ²⁴³₉₄Pu

Thus, the equation is:

²⁴⁷₉₆Cm —> ²⁴³₉₄Pu + ⁴₂He

From the illustrations above, the daughter nuclei formed is Plutonium-243 (²⁴³₉₄Pu)

Answer:

Plutonium-243

Explanation:

Answer:

Because the compound has a formula of M2O, the number of valence electrons of M should be 1. Therefore, (1) Group 1 is the correct answer because elements in group 1 have 1 valence electron.

Explanation:

Answer:

option B

hope it helps! please mark me brainliest

Answer:

Increase

Explanation:

Hope it helps you

Answer:

Decrease

Explanation:

If the oil you're referring to is just some normal oil, it'll lessen the friction and cause it to side more smoothly

Answer:

36 electrons

Explanation:

The # of protons is always equal to the atomic number. In the case of Sr (Strontium), it is 38 protons.

The 2+ at the end means that it has a charge of +2, meaning that it LOST two electrons to become a cation with a full valence shell. So, 38 - 2 = 36 electrons

Answer:

38 protons 36 electrons 30 neutron because of 29 isotope

Answer: $6,600[tex]\alpha \sqrt[n]{x} \lim_{n \to \infty} a_n[/tex]

Explanation:

Answer:

This description can be expressed as follows:

Y > W > XY>W>X

And,

W=ZW=Z

From these expressions we are able to find out that the saltiest cell description is Y, while the less salty is X.

Now, salt is well known as a dehydrating agent. In a process called osmosis cells placed in a salty liquid environment lose water, how?

Well, cells have a semipermeable membrane, in which some substances can get inside. Cells also have water inside. If a cell is placed in a quite salty liquid environment, salt will make the water inside the cells to come out, drying the cell and diminishing its size.

So, in this case, according to the expressions above, Cell Y will look the smallest, while cell X will look the biggest.

If we pour pure water in each liquid, the salt concentration will change and each cell will begin to grow bigger, but the saltiest cell will still be smaller than the others with less salt concentration.

Answer:

message me on messenger johnpatrick so I can help you

Answer:

[tex]C_{4}H_{10}O[/tex]

Explanation:

Hello!

In this case, since the empirical formula of compounds whose by-mass compositions are known, is computed by first computing the moles considering those compositions as actual masses:

[tex]n_C=\frac{64.82g}{12.01g/mol}=5.40mol\\\\n_H=\frac{13.62g}{1.01g/mol}=13.5mol\\\\n_O=\frac{21.58g}{16g/mol}=1.35mol[/tex]

Next, we divide each moles by the fewest ones, in this case those of oxygen to obtain the subscript in the empirical formula:

[tex]C=\frac{5.40}{1.35}= 4\\\\H=\frac{13.5}{1.35}=10\\\\O=\frac{1.35}{1.35}=1[/tex]

Thus, we obtain:

[tex]C_{4}H_{10}O[/tex]

Best regards

Answer:

kinetic energy I think so

The form of energy molecules have at the molecular level is Kinetic energy.

Kinetic energy is defined as the energy possessed by a body as a result of its motion or movement.

Molecules interact with one another through various movements that occur

within them. This happens to aid the formation of new substances in the

ecosystem. The three states of matter exhibit varying degree of movement

within its molecules.

The energy is usually in the form of chemical energy also and is the reason

why kinetic energy is the most suitable choice.

Read more on https://brainly.com/question/2627669

Answer:

By bonding due to the attractive forces

Answer:

6200 meters

Explanation:

To convert from km to m you have to multiply the number by a thousand

Answer:

6.2×10^3 m

Explanation:

6.20×1000=6200m

In scientific notation 6200 = 6.2×10^3

Answer:

I hope this helps!Good luck

Answer: The empirical formula is [tex]H_4P_2O_7[/tex]

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of H= 2.270 g

Mass of P = 34.80 g

Mass of O = 62.93 g

Step 1 : convert given masses into moles

Moles of H =  [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{2.270g}{1g/mol}=2.270[/tex]

Moles of P =  [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{34.80g}{31g/mol}=1.122[/tex]

Moles of O = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{62.93g}{16g/mol}=3.933[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For H =  [tex]\frac{2.270}{1.122}=2[/tex]

For P=    [tex]\frac{1.122}{1.122}=1[/tex]

For O =   [tex]\frac{3.933}{1.122}=3.5[/tex]

The simples ratio will be = H: P : O= 4: 2: 7

Hence the empirical formula is [tex]H_4P_2O_7[/tex]

Answer:

Explanation:

So chemical changes require a change on a molecular level that cannot be reversed because they form some new substance. Souring milk is not something you can reverse, and the process of it souring produces new molecules.

Answer:

5.44 moles of nitrogen required.

Explanation:

Given data:

Number of moles of NH₃ = 10.88 mol

Moles of N₂ required = ?

Solution:

Chemical equation:

N₂ +  3H₂         →       2NH₃

Now we will compare the moles nitrogen and hydrogen.

               NH₃          :           N₂

                 2             :           1

               10.88        :         1/2×10.88 = 5.44mol

5.44 moles of nitrogen required.

Answer:Vinegar

Explanation:

Answer: physically

Explanation: it's a physical change because the air that fills it up does not affect its chemical compound like I'd you mix metal in salt water

Answer:

C)2 mole Cu(NO3)2 / 2 mole Fe

Explanation:

I'm pretty sure.

When iron is combined with copper (1) nitrate, it produces iron (II) nitrate and copper. The following could NOT be a mole ratio in this chemical reaction is:

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

To determine which of the given mole ratios could NOT be part of the chemical reaction between iron and copper(1) nitrate, we need to write the balanced chemical equation for the reaction and then compare it to the given ratios.

The balanced chemical equation for the reaction is:

Fe + Cu(NO₃)₂ → Fe(NO₃)₂ + Cu

A) 1 mole Fe / 2 mole Cu

This mole ratio is consistent with the balanced chemical equation, where 1 mole of Fe reacts with 2 moles of Cu(NO₃)₂ to produce 1 mole of Fe(NO₃)₂ and 1 mole of Cu. So, this ratio could be part of the chemical reaction.

B) 1 mole Fe(NO₃)₂ / 2 mole Cu

This mole ratio is also consistent with the balanced chemical equation, where 1 mole of Fe(NO₃)₂ is produced by reacting 2 moles of Cu(NO₃)₂. So, this ratio could be part of the chemical reaction.

C) 2 mole Cu(NO₃)₂ / 2 mole Fe

This mole ratio is consistent with the balanced chemical equation, where 2 moles of Cu(NO₃)₂ react to produce 2 moles of Fe(NO₃)₂. So, this ratio could be part of the chemical reaction.

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

This mole ratio implies that 1 mole of Fe(NO₃)₂ is produced by reacting with 1 mole of Fe, which is not consistent with the balanced chemical equation. The equation shows that 1 mole of Fe reacts with 1 mole of Cu(NO₃)₂ to produce 1 mole of Fe(NO₃)₂ and 1 mole of Cu. Therefore, this ratio could NOT be part of the chemical reaction.

So, the correct answer is:

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

To know more about iron (II) nitrate here

https://brainly.com/question/31428625

#SPJ2

Answer:

Any element in group 1 has just one valence electron. Examples include hydrogen (H), lithium (Li), and sodium (Na). Any element in group 18 has eight valence electrons (except for helium, which has a total of just two electrons).

Explanation:

How many valence electrons does each element have?

The Group 1 atoms have 1 valence electron. The Group 2 atoms have 2 valence electrons. The Group 3 atoms have 3 valence electrons. The Group 4 atoms have 4 valence electrons.

I hope it's helpful

Answer: Temperature

Explanation:

Answer: Temperature

Explanation: can i get brainliest plss

Answer:

In gases are much more spread out than in solids or liquids. They vibrate and move freely at high speeds. A gas will fill any container, but if the container is not sealed, the gas will escape. Gas can be compressed much more easily than a liquid or solid.

Explanation:

Answer:

Electronegativity is probably the biggest thing that plays into reactivity. Therefore, since fluorine has a higher electronegativity than chlorine, fluorine is more reactive.

Explanation:

I got it right

2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Given

Standard cell notation:

Mg(s) | Mg2+ (aq) || Ag+(aq)| Ag(s)

Required

a balanced redox reaction

Solution

At the cathode the reduction reaction occurs, the anode oxidation reaction occurs

In reaction:  

Ag⁺ + Mg → Ag + Mg²⁺  

half-reactions

Ag⁺ (aq) + e⁻ ---> Ag (s)  x2

2Ag⁺ (aq) + 2e⁻ ---> 2Ag (s)

Mg (s) → Mg²⁺ (aq) + 2e−

a balanced cell reaction

2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Answer:2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Explanation:

just took test

Answer:

4.99*10²³ molecules of N₂O₄ are in 76.3 g of N₂O₄

Explanation:

Avogadro's Number is the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023*10²³ particles per mole. Avogadro's number represents a quantity without an associated physical dimension. Avogadro's number applies to any substance.

You know that the molar mass of N₂O₄ is 92.02 g/mol, and you have 76.3 g. Then you can apply the following rule of three: 92.02 grams are present in 1 mole of the compound, 76.3 grams in how many moles are they?

[tex]amount of moles= \frac{76.3 grams*1 mole}{92.02 grams}[/tex]

amount of moles= 0.83 moles

Then, you can apply another rule of three: if by definition of Avogadro's number 1 mole of the compound has 6.023*10²³ molecules, 0.83 moles of the compound, how many molecules will it have?

[tex]amount of molecules= \frac{0.83 moles*6.023*10^{23}molecules }{1 mole}[/tex]

amount of molecules= 4.99*10²³

4.99*10²³ molecules of N₂O₄ are in 76.3 g of N₂O₄

Answer:

each planet has a different force of gravity

Explanation:

Weight = mass× gravity

As gravity changes from place to place and also from planet to planet so weight changes.

Answer:

1413.386

Explanation: