Can somebody plz help with Grade7science!!

Plz answer this question and explain why it’s the best? (Any energy:

WILL MARK BRAINLIEST WHOEVER ANSWERS FIRST :DD

Answer:

In 2 grams of NaCl are 116,88 mols

Explanation:

One mol of NaCl (6.02 x1023 formulas) has a mass of 58.44 g.

Calculation: 58,44g X 2 = 116,88

Answer:

Carbon

Explanation:

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Answer:

Fe, or the iron atom

Explanation:

The subscripts designate the number of atoms in the molecule. If there is no subscript, it is understood to be 1.

Answer: 1024 sodium ions

Explanation: The mathematical equation, N = n × NA, can be used to find the number of atoms, ions or molecules in any amount (in moles) of atoms, ions or molecules: 10 moles of helium atoms = 10 × (6.022 × 1023) = 6.022 × 1024 helium atoms. 10 moles of sodium ions = 10 × (6.022 × 1023) = 6.022 × 1024 sodium ions. (that took long)

Answer:

earth

Explanation:

water vapor, water, ice

Answer:

Option C: Combustion and synthesis only

Explanation:

This reaction is referred to as combustion reaction because carbon is burnt in oxygen to produce carbon (IV) oxide.

Also, it's a synthesis reaction because the two different atoms which are Carbon and oxygen interact to form a different compound which is CO2.

Thus, the correct answer is Option C: combustion and synthesis only

Answer:

According to Kinetic Molecular Theory, an increase in temperature will increase the average kinetic energy of the molecules. As the particles move faster, they will likely hit the edge of the container more often. If the reaction is kept at constant pressure, they must stay farther apart, and an increase in volume will compensate for the increase in particle collision with the surface of the container.

Explanation:

Answer:

well, it made volcanos grow larger and it developed land

Explanation:

Gases and solids injected into the stratosphere circled the globe for three weeks. Volcanic eruptions of this magnitude can impact global climate, reducing the amount of solar radiation reaching the Earth's surface, lowering temperatures in the troposphere, and changing atmospheric circulation patterns.

Answer:

The correct answer is - control rods.

Explanation:

Control rods are filled with special absorbing agents such as boron, cadmium, silver, and others to absorb as many neutrons as to control the fission reaction by moving them up and down in between uranium rods.

These control rods are used to prevent the nuclear reaction from getting out of control in the nuclear plant or reactor by absorbing the neutrons and prevent uranium to convert.

Given that,

Temperature, T = 1500 K

Wavelength, [tex]\lambda=4.5\times 10^2\ nm[/tex]

To find,

The energy of one photon of this light.

Solution,

We know that, the energy of a photon is given by the formula as follows :

[tex]E=\dfrac{hc}{\lambda}\\\\E=\dfrac{6.63\times 10^{-34}\times 3\times 10^8}{4.5\times 10^2\times 10^{-9}}\\\\=4.42\times 10^{-19}\ J[/tex]

So, the required energy is [tex]4.42\times 10^{-19}\ J[/tex].

Answer:

The ions are held together by ionic bonds, which form an ionic compound. Ionic compounds generally form between elements that are metals and elements that are nonmetals. For example, the metal calcium (Ca) and the nonmetal chlorine (Cl) form the ionic compound calcium chloride (CaCl2)

Explanation:

Answer:

¹⁴₇N

Explanation:

⁴₆C → ¹⁴₇N + ⁰₋₁e

The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.

Beta radiations:

Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.

The mass of beta particle is smaller than the alpha particles.

They can travel in air in few meter distance.

These radiations can penetrate into the human skin.

The sheet of aluminum is used to block the beta radiation

The new volume : V₂ =  2454.8 L

Given

V₁=2240 L

P₁=760 mmHg

T₁=320 K

P₂=700 mmHg

T₂=323 K

Required

Volume V₂

Solution

Combined gas law :

P₁V₁/T₁=P₂V₂/T₂

Input the value :

760 mmHg x 2240 L /320 K = 700 mmHg x V₂/323 K

V₂=(P₁V₁T₂)/P₂T₁

V₂=(760 x 2240 x 323)/(700 x 320)

V₂ = 2454.8 L

Yes, a metal will always be produced at one electrode during electrolysis.

An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit.

An electrode can be anode or cathode. During electrolysis, that is , the decomposition of a chemical compound by electricity, a metal will be deposited at the cathode.

Thus, a metal will always be produced at one electrode during electrolysis.

Learn more about electrolysis here: https://brainly.com/question/25712870

#SPJ1

Answer: FALSE

Explanation: Often, gases rather than metals form at electrodes, especially if it involves the electrolysis of a solution.

Answer:

density=mass/volume

Explanation:

density is defined as mass per unit volume.

Answer:

Yes

Explanation:

Atoms are generally classified as pure substances. A pure substance has the following properties:

Elements and compounds are generally classified as pure substances. Since atoms are the building blocks of pure substances, they can be classified as one.

Answer:

964ug

Explanation:

The problem here involves converting from one unit to another.

 We are to convert from ounces to micrograms.

                                    1ug  = 1 x 10⁻⁶g

                                    1oz  = 28.35g

So we first convert to grams from oz then take to ug:

 Solving:

                    1oz  = 28.35g

             3.4 x 10⁻⁵oz  will then give  3.4 x 10⁻⁵ x 28.35 = 9.64  x 10⁻⁴g

So;

                    1 x 10⁻⁶g    = 1ug

          9.64  x 10⁻⁴g will give [tex]\frac{9.64 x 10^{-4} }{1 x 10^{-6} }[/tex]      = 9.64 x 10²ug or 964ug

Answer:

That’s a question on school- what- I-

Explanation:

Answer: D sand and water

Explanation:

Since water is less dense than sand it could be easily separated if you go to the ocean that’s why the water is at the bottom of the sand but on above the sand so it will be able to separate easily.

Answer:

Answer: D sand and water

Explanation:

Answer:

Thermal insulation. Thermal insulation is the reduction of heat transfer (i.e. the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence.

Explanation:

Answer:

The job of a thermal insulator is to reduce the heat transfer

Explanation:

Answer:

a) Number of moles = 0.41 mol

b) Number of moles = 0.44 mol

c) Number of moles = 0.47 mol

Explanation:

a)

Given data:

Mass of copper sulfate = 65.5 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass of copper sulfate = 159.6 g/mol

Number of moles = 65.5 g/ 159.6 g/mol

Number of moles = 0.41 mol

b)

Given data:

Mass of magnesium nitrate  = 65.5 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass of magnesium nitrate = 148.3 g/mol

Number of moles = 65.5 g/148.3g/mol

Number of moles = 0.44 mol

c)

Given data:

Mass of potassium carbonate  = 65.5 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass of potassium carbonate = 138.2 g/mol

Number of moles = 65.5 g/138.2g/mol

Number of moles = 0.47 mol

Answer:

You can change an object's state of matter by adding or removing thermal energy. When you add thermal energy to an object, these things can happen: Particles move faster

Explanation:

Answer:

25

Explanation:

mass number = protons + neutrons

= 13 + 12 = 25

Overall, an atom is neutral charged. The Bohr model was for years accepted as the final authority because it agrees so well with experiment and observation. In this model an atom consists of a nucleus containing protons and neutrons. The neutrons are zero charge so we can forget them in looking for charges. For each proton (1 positive charge) there is always 1 electron (1 negative charge) in orbit around the nucleus. thus an atom has a equal number of electrons and protons and their net charge is zero.

We can do things to temporarily up set this natural balance (we call this electricity) but the atoms will eventually return to their naturally balanced state