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3 years ago

Which of these relationships is true of an uncharged atom?

Chemistry

1 answer:

marusya05 [52]3 years ago

7 0

Answer:

The correct option is C) The number of protons is equal to the number of electrons.

Explanation:

Atoms are made up of particles called protons, neutrons, and electrons. Protons and neutrons are in the center of the atom and form the nucleus, while electrons surround the nucleus. Electrons have a negative charge. The charge of the protons is positive and finally, the neutrons have no charge.

If the atom has no charge, this means that the total charge of the atomic nucleus, which is positive due to the presence of the protons, is equal to the negative charge of the electrons, so that it cancels out.

So, the correct option is C) The number of protons is equal to the number of electrons.

You might be interested in

Liquid bromine is added to sodium iodide crystals

gulaghasi [49]

The following chemical reaction will occur:

Br₂ (l) + 2 NaI (s) → 2 NaBr (s) + I₂ (s)

Explanation:

Because the bromide (Br₂) have a higher reactivity than iodide (I₂) it is able the remove the iodide from its salts. So the bromide will react with sodium iodine (NaI) to produce sodium bromide (NaBr) and iodine.

The chemical reaction is:

Br₂ (l) + 2 NaI (s) → 2 NaBr (s) + I₂ (s)

where:

(l) - liquid

(s) - solid

Learn more about:

balancing chemical equations

brainly.com/question/13971935

#learnwithBrainly

6 0

3 years ago

If the half-life of 37Rb is 4.7x101 years, how long would it take for 0.5 grams of a 2 gram sample to radioactively decay?

k0ka [10]

Answer: The time required will be 19.18 years

Explanation:

All the radioactive reactions follows first order kinetics.

The equation used to calculate half life for first order kinetics:

$k=\frac{0.693}{t_{1/2}}$

We are given:

$t_{1/2}=4.7\times 10^1yrs$

Putting values in above equation, we get:

$k=\frac{0.693}{4.7\times 10^1yr}=0.015yr^{-1}$

Rate law expression for first order kinetics is given by the equation:

$k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}$

where,

k = rate constant = $0.015yr^{-1}$

t = time taken for decay process = ?

$[A_o]$ = initial amount of the reactant = 2 g

[A] = amount left after decay process = (2 - 0.5) = 1.5 g

Putting values in above equation, we get:

$0.015yr^{-1}=\frac{2.303}{t}\log\frac{2}{1.5}\\\\t=19.18yrs$

Hence, the time required will be 19.18 years

4 0

3 years ago

10. Which of the following consists of two or more pure substances?

Hunter-Best [27]

I am 100% sure it’s oxygen

8 0

3 years ago

Calculate the wavelength of light emitted when each of the following transitions occur in the hydrogen atom. What type of electr

Len [333]

Answer:

a. 1875 nm

b. 4051 nm

c. 1282 nm

These all are infrared electromagnetic radiation.

Explanation:

Our strategy here is to utilize the Rydberg equation for hydrogen atom electronic transition.

1/λ = Rh x (1/n₁² - 1/n₂²) where λ is the wavelength

Rh is Rydberg constant

n₁ and n ₂ are the energy levels ( n₁ < n₂ )

Now lets star the calculations.

a. n₁ = 3, n₂ = 4

1/λ = 1.097 x 10⁷ /m x (1/3² - 1/4²) = 5.333 x 10⁵/m

λ = 1/(5.333 x 10⁵ /m) = 1.875 x 10⁻⁶ m

Converting λ to nanometers:

1.875 x 10⁻⁶ m x (1 x10⁹ nm/m) = 1875 nm

b. n₁ = 4, n₂ = 5

1/λ = 1.097 x 10⁷ /m x (1/4² - 1/5²) = 2.468 x 10⁵/m

λ = 1/(2.468 x 10⁵/m) = 4.051 x 10⁻⁶ m

4.051 x 10⁻⁶ m x (1 x10⁹ nm/m) = 4051 nm

c. n₁ = 3, n₂ = 5

1/λ = 1.097 x 10⁷ /m x (1/3² - 1/5²) = 7801 x 10⁵/m

λ = 1/(7801 x 10⁵/m) = 1282 x 10⁻⁶ m

1282 x 10⁻⁶ m x (1 x10⁹ nm/m) = 1282 nm

All of these transitions fall in the infrared region of the spectrum.

8 0

3 years ago

What is the boiling point of cyclohexane at 620 mmhg? can you show calculations?

Anton [14]

Boiling point of cyclohexane at 620 mm hg?

Standard atmospheric pressure is 760 mm Hg. Boiling point at 760 mm= 80.74˚C

A liquid boils when its vapor pressure is equal to the atmospheric pressure. The vapor pressure of a liquid is proportional the absolute temperature of the liquid.

As the atmospheric pressure decreases, less vapor pressure is needed to cause the liquid to boil. Less vapor pressure means lower temperature.

The boiling point of cyclohexane at 620 mm Hg is less than 80.74˚C

TRY THAT OR THIS

271.78

7 0

3 years ago

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