Contrast exo. and endothermic reactions and give an example for each?

Answer:

There are 5.69*10²⁴ molecules in 9.45 moles.

Explanation:

The mole is defined as the amount of matter that particles have, that is, atoms and elementary entities.

Avogadro's Number or Avogadro's Constant is called 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 and represents a quantity without an associated physical dimension. Avogadro's number applies to any substance.

Then the following rule of three can be applied: if 1 mole contains 6.023 * 10²³ molecules, 9.45 moles, how many molecules will it have?

[tex]amount of molecules=\frac{9.45 moles*6.023*10^{23}molecules }{1 mole}[/tex]

Solving:

amount of molecules= 5.69*10²⁴⁴ molecules

There are 5.69*10²⁴ molecules in 9.45 moles.

Answer:

Carbon dioxide or co^2

Explanation:

Answer:

Ring is made up off copper.

Explanation:

Given data:

Mass of ring = 89.2 g

Volume of water = 10 mL

Volume of water + ring = 20 mL

Ring is made up of = ?

Solution:

Volume of ring = (Volume of water + ring) - Volume of water

Volume of ring = 20 mL - 10 mL

Volume of ring = 10 mL

Density:

Density = mass/volume     ( 1 mL = 1 cm³)

d = 89.2 g/  10cm³

d = 8.92 g/cm³

Thus, ring is made up off copper.

Electron pairs around a central atom arrange themselves so that they can be as far apart as possible from each other. The repulsion between negatively charged electrons pairs in bonds or as lone pairs causes them to spread apart as much as possible

Explanation:

Answer:

Wouldn't rust because zinc will lose electrons more readily than iron and will therefore oxidize first.

Explanation:

This process whereby rusting of steel is prevented by coating the steel with a layer of zinc is known as galvanization.

Now, in this process, the steel object will be coated in a thin layer of zinc. This coating will prevent oxygen and water from reaching the underneath metal since the zinc will also act as a sacrificial metal.

Now, Zinc is used because it has a lower reduction potential than iron and thus it will get easily more oxidized than iron. Which means the zinc will lose electrons more readily than iron.

Also, since zinc has a lower reduction potential, it is therefore the more active metal. Thus, even if the zinc coating is scratched and the steel is exposed to moist air, the zinc will still get to oxidize before the iron.

Ao H+HH OH

santa said he will eat shower curtian at 2 am

Answer:

3.193 mol

Explanation:

The reaction is

[tex]N_2+3H_2\rightarrow 2NH_3[/tex]

We use the stoichiometry in order to find the moles of nitrogen required.

[tex]9.58\ \text{mol of }NH_3\times \dfrac{1\ \text{mol of }N_2}{2\ \text{mol of }NH_3}[/tex]

[tex]=3.193\ \text{mol of }N_1[/tex]

The amount of nitrogen required is 3.193 mol to produce 9.58 mol of ammonia.

Answer:

The Plasma Membrane.

Explanation:

The eukoryotic cell is enclosed in a limiting membrane called the Plasma Membrane or Plasmalemma. ❤️

Answer:

a one rotation of the planet on its axis

Explanation:

The two types of motion that planets undergo are;

1) rotation of the planet about its axis

2) revolution of the planet around the sun.

In every planet there are days as shown in the image attached to the question. However, the length of day in each planet is determined by the time required for the planet to complete one rotation on its axis.

It takes the earth 1 earth day (24 hours) to complete rotation on its axis.

Answer:

Jupiter would have the strongest gravitational pull on a satellite.

Gravity is directly proportional to mass.

Jupiter is the most massive, so it will have a stronger gravitational pull.

Explanation:

The molar mass of B(NO₃)₃ - Boron nitrate : 196.822 g/mol

In stochiometry therein includes  

Relative atomic mass (Ar) and relative molecular mass / molar mass (M)  

So the molar mass of a compound is given by the sum of the relative atomic mass of Ar  

M AxBy = (x.Ar A + y. Ar B)  

The molar mass of B(NO₃)₃ - Boron nitrate :

M B(NO₃)₃ = Ar B + 3. Ar N + 9.Ar O

M B(NO₃)₃ = 10.811 + 3. 14,0067 + 9. 15,999

M B(NO₃)₃ = 196.822 g/mol

Answer:

Nonmetals are further to the right on the periodic table, and have high ionization energies and high electron affinities, so they gain electrons relatively easily, and lose them with difficulty.

Explanation:

They also have a larger number of valence electrons, and are already close to having a complete octet of eight electrons.

Periodic table is divided as metals, non metals, noble gases and semiconductors. Among these nonmetals tend to have high electron affinities because of small size and high effective nuclear charge.

Non metals are the element that have property to gain electron. When any element gain electron then element attain negative charge and that element is called anion.

As we go from left to right in periodic table, the size of element decreases as number of electrons keep on adding electrons in the same shell . As the number of electrons increases, the number of proton in the nucleus also increases. Due to this, the hold of nucleus on the outermost proton increases and the size decreases. Due to this, the ionization energy increases and hence the power to gain electron increases.

Therefore, nonmetals tend to have high electron affinities because of small size and high effective nuclear charge.

To learn more about non metals, here:

https://brainly.com/question/28650063

#SPJ2

Answer:

3.37 × 10²³ molecules

Explanation:

Given data:

Mass of C₆H₁₂O₆ = 100 g

Number of molecules = ?

Solution:

Number of moles of C₆H₁₂O₆:

Number of moles = mass/molar mass

Number of moles = 100 g/ 180.16 g/mol

Number of moles = 0.56 mol

Number of molecules:

1 mole contain 6.022 × 10²³ molecules

0.56 mol × 6.022 × 10²³ molecules /1 mol

3.37 × 10²³ molecules

Answer:

the answer should be c.

Explanation:

Answer: P represents electrical energy, Q represents thermal energy.

Explanation: The toaster takes electrical energy from the electrical socket through wires and converts that into thermal energy that heats up/toasts the bread.

Answer:

P represents electrical energy, Q represents thermal energy

Explanation:

I am sorry if I get this wrong, but when I put it in the sentence - A toaster transforms electrical energy into thermal energy - it made sense to me, so I think that is the answer. I am sorry if this does not help.

Answer:

12 number of moles of carbon dioxide are used.

Explanation:

Given data:

Number of moles of oxygen produced = 12 mol

Number of moles of CO₂ used = ?

Solution:

Chemical equation:

6CO₂ + 6H₂O      →     C₆H₁₂O₆ + 6O₂

Now we will compare the moles of oxygen with carbon dioxide.

                     O₂            :          CO₂

                      6             :             6

                    12              :             12

Thus, 12 number of moles of carbon dioxide are used.

Answer:

The chemistry between you will be instant. Sometimes it may be hard to know if they like you back. Knowing that you can not live without them and that you bump in to each other everywhere you go, is fate at work. You might also just need the courage to ask them out. You never know what will happen if you try. :)

Answer:

You will feel it

Explanation:

Answer:

30 grams

Explanation:

I got 40 wrong so I picked 30

Answer:

30 grams

Explanation:

I did the ck12

Answer:

Average atomic mass of uranium = 237.97 amu

Explanation:

Given data:

Abundance of U-234 = 0.01%

Abundance of U-235 = 0.71%

Abundance of U-238 = 99.28%

Average atomic mass of uranium = ?

Solution:

Average atomic mass  = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass)  / 100

Average atomic mass  = (234×0.01)+(235×0.71)+(238+99.28) /100

Average atomic mass =  2.34 + 166.85+23628.64 / 100

Average atomic mass = 23797.83 / 100

Average atomic mass = 237.97 amu.

Answer:

Light and heat

ur welcomeeeeeeee

Answer:

Light and Heat

Give the other guy brainiest

Explanation:

Thx for the point though

Answer:

A im pretty sure

Explanation:

Answer:

not

medium

Explanation:

Light radiation travels as a wave and does not require a medium for travel. Like all electromagnetic radiations, light does not need medium particles for its propagation.

Answer:

kf

Explanation:

Answer: When an atom becomes a positive ion it pulls it's electrons closer, decreasing it's radius moreover, when it becomes a negative ion, it pulls it's electrons closer and decreases the radius

I hope this helps :)

Mass of water needed : 96.3 g

A mole is a number of particles(atoms, molecules, ions)  in a substance

This refers to the atomic total of the 12 gr C-12  which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles  

Can be formulated :

N = n x No

N = number of particles

n = mol

No = 6.02.10²³ = Avogadro's number

moles H₂O=

[tex]\tt moles=\dfrac{N}{No}\\\\moles=\dfrac{3.22\times 10^{24}}{6.02\times 10^{23}}\\\\moles=5.35[/tex]

mass H₂O(MW=18 g/mol) :

[tex]\tt mass=moles\times MW\\\\mass=5.35\times 18\\\\mass=96.3~g[/tex]

when liquid water changes into solid ice, it increases in mass