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Answer:

combustion of car engines producing pollutants in the air

Answer:

lol☺️☺️☺️☺️☺️☺️☺️☺️

Explanation:

protons have a relative charge of +1, they are located in the nucleus and the carry a positive charge

the electrons are negatively charged and have a charge of -1 . They are found orbiting on the shells .the electrons have a negligible mass of 1 / 1840

the neutrons have no charge they are located in the nucleus of an atom .

Answer:

Chemical elements are categorized in the Periodic Table based on the number of protons and electrons. The electrons are the sub-atomic particle, which revolves around the atomic nucleus and has a negative charge. The protons are the positive charged sub-atomic particles, which are present in the nucleus of the atom.

Explanation:

The chemical element is a pure particle, which is made up of atoms. The atoms in a neutral chemical element have the same number of electrons and protons. In the case given above, calcium has fewer protons and electrons than rubidium. Calcium has the atomic number 20, such that it belongs to group 2 and period 4. The number of electrons and protons in calcium (no net charge) is 20. Similarly, the rubidium belongs to group 1 and period 5. The element has the atomic number 37, such that the number of electrons and protons in rubidium is 37.

Answer:

the number of protons is called the atomic number

hope it helps you buddy

Answer: number of protons in an atom

Explanation:

Answer:

Melting poing is the temperature at which a solid changes to liquid under atmospheric pressure. Freezing point is the temperature at which liquid changes to solid under atmospheric pressure.

Elements are substances that are made from one type of atom. An element cannot be broken down into any other substance. ... Compounds are substances made from atoms of different elements joined by chemical bonds. They can only be separated by a chemical reaction.

Compounds are formed because of chemical bonding between two elements. Mixtures are formed when substances are physically mixed with one another. Compounds are basically of three kinds : Ionic, metallic and covalent

Answer:

11. A

12. B

13. D

14. E

15. C

Answer:

1) chemical indicators won't work above it's pH range so therefore it probably won't change colour.

2) the solution should be clear and colourless to see colour change.

3) indicators tend to be of low accuracy so it's not 100% reliable.

Given that the radius of a silver atom is 145 pm, it would take [tex]7.97 \times 10^{6}[/tex] silver atoms laid side by side to span a distance of 2.31 mm.

The radius of a silver atom is 145 pm. Then, the diameter (twice the radius) is:

[tex]d = 2 \times 145 pm = 290 pm[/tex]

We will convert 290 pm to millimeters. We will use the conversion factors:

[tex]290 pm \times \frac{1m}{10^{12}pm } \times \frac{10^{3}mm }{1m} = 2.90 \times 10^{-7} mm[/tex]

If the diameter of 1 silver atom is 2.90 × 10⁻⁷ mm, the number of silver atoms required to span a distance of 2.31 mm is:

[tex]2.31 mm \times \frac{1Ag\ atom}{2.90 \times 10^{-7}mm } = 7.97 \times 10^{6} Ag\ atom[/tex]

[tex]7.97 \times 10^{6}[/tex] silver atoms span a distance of 2.31 mm.

You can learn more about unit conversions here: brainly.com/question/19420601

ANSWER:

We can convert methanol into ethanol by an organic coupling reaction which is called Wurtz reaction. This is carried out with sodium metal in the presence of dry ether and forms higher alkanes.

Answer:

Ethylenediaminetetraacetic acid (EDTA), heparin, and citrate are the most commonly used anticoagulants (39–41). pls mark me branilest

Answer:nb mhvj

Explanation:

hvvmjhv

Answer: angular

Explanation:

Angular and is found in hydrogen...from sighwell assumption saying that is they is three pairs of electrons in the valence shell of the central atom the orbital will oriente at an angle of 120° to form a bond of trigonal planar or angular.

Answer:

1) ball and stick is right just did this on my test.

2) linear

Explanation:

Answer:

c

Explanation:

took test on usa testprep

When gas in a discharge tube is excited to higher energy level after some seconds they return to the ground level by releasing energy in the form of light. Thus energy jumps by electron due to excitation is correct option.

A gas discharge tube is an electronic devise containing inert gases that ionizes and conducts results in  emission of light.

When a potential  is applied between the electrodes in a gas discharge tube, and the pressure is reduced, the gas particles inside forms a plasma of ions.

The electrons released when excited to higher energy level by absorbing energy and returns to the initial state by emitting energy in the form of light, the discharge tube glows.

The color emitted by the discharge tube vary based on the gas in the tube. Each type of gaseous ions emit different colors.

Therefore, the light emission in gas discharge tube is due to energy hike during electron excitation and then relaxing by emitting the light energy. Thus, option c is correct.

To find more about gas-discharge tube, refer the link below:

https://brainly.com/question/5468708

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Answer:

the other variable is also doubled

Explanation:

direct proportion, same thing has to happen to both variables

Answer:

930 pls mark me branilest

Answer:

11.0117647

Explanation:

Answer:

Explanation:

Quantatative is when a number of something changes, and we could sometimes visualize it, but qualitative is different.

Hope this helps

kenny

:D

Answer:

The dependant variable

Explanation:

The dependent variable is the factor that is being tested and measured in an experiment.

Answer:

0.44mol

Explanation:

1mol/102g=xmol/45.1g

-> x=(45.1x1)/102

x=0.44mol

Answer:

Fine chemicals are used as starting materials for specialty chemicals, particularly pharmaceuticals, biopharmaceuticals and agrochemicals. ... The term "fine chemicals" is used in distinction to "heavy chemicals", which are produced and handled in large lots and are often in a crude state.

Explanation:

Answer:

10 ml

Explanation:

The graduated cylinder contains 19 ml of water before the silver pellet is placed inside. Afterwards, the graduated cylinder measures 29 ml of water. Therefore the pellet displaced 10 ml of water. ( 29ml - 19ml = 10ml )

Answer:

13.7 cm

Explanation:

If the number is between two whole numbers then that means it is going to be a decimal, how to determine the decimal is by how many ticks/lines are between it, so if you count from 13 cm and count each line as 1 you get to the number 7 and since that number is between the whole number it becomes 13.7

The correct answer is: Avogadro

The Avogadro constant (NA or L) is the proportionality factor that relates the number of constituent particles (usually molecules, atoms or ions) in a sample with the amount of substance in that sample. Its SI unit is the reciprocal mole, and it is defined as NA = 6.02214076×1023 mol−1.

The answer is Avogadro.

Explanation:

Here are the examples :

The mass of a single carbon-12 atom has been found to be 1.992×10^-23 g using a mass spectrometer. The number of atoms in exactly one mole of 12C is 6.02×10^23. This can be shown by the following calculation.

Na = Mass per mole of 12C ÷ Mass of one atom of 12C

= 12g/mol ÷ 1.992×10^-23

= 6.02 × 10^23 mol^-1

Thus one mole of any substance contains 6.02×10^23 particles. This number is called the Avogadro constant.

So that 12g of the element carbon , 1 g of the element hydrogen and 32g of the element sulphur contains 6.02×10^23 atoms even though the element carbon exist as atoms, and Hydrogen and sulphur exist as molecules.

I hope it can help you

Cu2+ is the correct answer!

Answer:

[tex]{ \sf{A \: and \: C \: \: only }}[/tex]