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Answer: Eggshells have a similar chemical composition to our tooth enamel, making them react similarly with other chemicals. This can help us understand what stains tooth enamel. When we brush an eggshell with fluoridated toothpaste, it strengthens the shell and protects it from acid, just like it does for our tooth enamel

Explanation:

Answer: Eggshells have a similar chemical composition to our tooth enamel, making them react similarly with other chemicals. This can help us understand what stains tooth enamel. When we brush an eggshell with fluoridated toothpaste, it strengthens the shell and protects it from acid, just like it does for our tooth enamel.

Answer:

[tex]\boxed {\boxed {\sf C. \ 30 \ m/s \ east}}[/tex]

Explanation:

Velocity is the vector measurement of the change in position over time. A vector measurement means the answer must include a magnitude (numerical value) and a direction.

Here are some units of velocity:

There are many other units, but m/s is the most common.

We can eliminate choice B and D, because the units (meters-m and meters per second squared-m/s²) are not for velocity.

We are left with choice A (30 m/s) and C (30 m/s east). Remember, velocity needs a number and a direction. C contains the direction east, so it must be the correct answer.  

Answer:

Solid particles are close together not gas particles

Answer:

its true

Explanation:

because I made sure it was true and it is

Answer:

running helps my heart beat

Answer:

Exercise: The easiest and most effective way to achieve a lasting lower heart rate is to do regular exercise. 2. Stay hydrated: When the body is dehydrated, the heart has to work harder to stabilize blood flow. Throughout the day, drink plenty of sugar- and caffeine-free beverages, such as water and herbal tea.

Answer:

169.913616 g/mol

Explanation: This is weight of AsF5 molecular weight

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Volume of Sodium metal : 20.454 ml

Reaction(balanced) :

2Na + 2H₂O → 2NaOH + H₂

mass NaOH = 34.5 g

mol NaOH(MW=40 g/mol) :

[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{34.5}{40}\\\\mol=0.8625[/tex]

From the equation, mol ratio of Na : NaOH = 2 : 2, so mol Na=mol NaOH=0.8625

Mass Na (Ar=23 g/mol):

[tex]\tt mass=mol\times MW\\\\mass=0.8625\times 23\\\\mass=19.84~g[/tex]

Volume Na :

[tex]\tt V=\dfrac{m}{\rho}\\\\V=\dfrac{19.84~g}{0.97~g/ml}\\\\V=20.454~ml[/tex]

State​ physical property can be used to distinguish between a 1 cm cube of copper and a 1 cm cube of sugar. Hence, option D is correct.

A property (such as colour, hardness, boiling point) of the matter is not involved in its manifestation of a chemical change.

Physical properties are those general properties you notice most readily about a substance, such as its size, state of matter (solid, liquid, or gas), colour, mass, density and strength.

Values for physical properties can be determined by tests that don't alter the substance being tested.

Hence, state​ physical property can be used to distinguish between a 1 cm cube of copper and a 1 cm cube of sugar.

Learn more about the physical property here:

https://brainly.com/question/18327661

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Answer:

2.19moles

Explanation:

mole = mass ÷ molar mass

Molar Mass of the compound, C135H96O9NS =

12(135) + 1(96) + 16(9) + 14 + 32

= 1620 + 96 + 144 + 14 + 32

= 1906g/mol

Next, we calculate the mass percent of Oxygen in the compound

O9 = 16(9) = 144g/mol

144/1906 × 100

= 0.0755 × 100

= 7.55%

This means that there are 0.0755g of Oxygen in 1 mole of the coal compound.

Hence, in 29.1 moles of coal, there would be 29.1 × 0.0755

= 2.19moles of Oxygen

Answer:

Explanation:

All matter is made up of atoms. ... These shells are actually different energy levels and within the energy levels, the electrons orbit the nucleus of the atom. The ground state of an electron, the energy level it normally occupies, is the state of lowest energy for that electron.

Answer:

B. Fan

Explanation:

The device in the options which converts electrical energy to kinetic

energy is the Fan.

When the fan is plugged to a an electric power source, the electrical energy gets converted to kinetic energy as a result of the movement of the blades in which Kinetic energy is defined as the energy as a result of the motion of a particle or substance.

It becomes a positives atom. Since it loses electrons it has more of a positive charge than a normal atom.

Answer:

1.223 g/ml

Explanation:

Answer:

Beta particles have a charge of minus 1.

Explanation:

Hope this helps!

Answer:

MARK AS BRAINLIEST ANSWER

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Explanation:

Beta particles have a mass which is half of one thousandth of the mass of a proton and carry either a single negative (electron) or positive (positron) charge. As they have a small mass and can be released with high energy, they can reach relativistic speeds (close to the speed of light)

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Answer: Science process skills include observing qualities, measuring quantities, sorting/classifying, inferring, predicting, experimenting, and communicating.

Answer:

It should be 9

Explanation:

That’s how I remember drawing them I took chemistry last year. Tell me if it’s good.

Answer:

A

Explanation:

Answer:

it's ductility and it's conductivity

Explanation:

Answer:

Hydration

Explanation:

* 2-propanol is converted to propene using heated alumina beads as the catalyst. The product gas is purified with a dry ice–propanol cold trap.

* the propene is hydrogenated to propane using a palladium catalyst in nearly 100% yield

Answer/Explanation:

The kinetic energy of a particle is one-half the product of the particle's mass m and the square of its speed v: K=12mv2.

Answer:

- Daniel- Earth and Space

- Sanya- Chemistry

Explanation:

Daniel's study field is associated with the 'Earth and Space' as he is attempting to explore how the frequency of tropical storms(in the atmosphere) and coastal erosion(relation with land and ocean) are interconnected to each other. He studies how the two are associated and affect life on the planet.

While Sanya's field of study would be 'Chemistry' as she aims to study the composition and constitution of substances and the changes that they undergo as a consequence of alterations in the constitution of their molecules('whether the discharge from industrial plants has any impact on the pH concentration of freshwater swamps in the surrounding area').

The balanced reaction is

4 Al + 3 O₂   →   2 Al₂O₃

so that for every 4 moles of Al and 3 moles of O2, you end up with 2 moles of Al₂O₃.

• Al has molar mass ≈ 26.982 g/mol

• O has molar mass ≈ 15.999 g/mol

• Al₂O₃ thus has molar mass ≈ 101.961 g/mol

You start with 5.4 kg = 5,400 g of Al, or

(5.4 kg Al) • (1/26.982 mol/g) ≈ 200.133 mol Al

Al₂O₃ is produced in a ratio of 2 moles to every 4 moles of Al, so you end up with about 100.067 mol Al₂O₃, which has a mass of

(100.067 mol Al₂O₃) • (101.961 g/mol) ≈ 10,202 g = 10.2 kg

so the answer is C.

Answer:

running a business is the best i have ever done to make a good friend of yours to get to the point where you have a lot to say

Answer:

carboxylic acid is the answer

Explanation:

Plz mark brainliest

Answer:

219 mmHg

Explanation:

The partial pressure of a gas refers to the pressure exerted by one of the gases in a mixture of gases.

The total pressure of a gas is the sum of all the partial pressures of all the gases in the mixture.

Since the total pressure = 745 mmHg

The partial pressure of helium is;

745 - (125 + 214 + 187)

Partial Pressure of helium gas= 219 mmHg