All categories

3 years ago

The temperature at which a substance freezes is called its melting point. True or False

Chemistry

1 answer:

Reika [66]3 years ago

5 0

False it would be freezing point

You might be interested in

A positron is emitted when ____________. *

Darina [25.2K]

The correct answer is:
a positron is emitted when proton converts to a neutron.

The reaction can be described as following:
₁¹p (proton) → ₀¹n (neutron) + ₁°e (positron or ₁⁰β)
Positron is an antiparticle of a β particle (₋₁°β), which means it has an oposite charge to it, but same mass.

7 0

3 years ago

A potassium hydroxide (KOH) solution has a molar concentration of 0.065 M, calculate the [H3O+], [OH-] and pH of the solution.

Tanya [424]

Answer:

1) [OH⁻] = 0.065 M

2) [H₃O⁺] = 1.54 x 10⁻¹³ M.

3) pH = 12.81.

Explanation:

HCl is completely dissociated yo its ions in solution:

1) [OH⁻] = 0.065 M.

∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.

∴ [H₃O⁺] = 10⁻¹⁴/[OH⁻] = 10⁻¹⁴/(0.065 M) = 1.54 x 10⁻¹³ M.

For strong acids like HCl:

pH = - log[H₃O⁺] = - log[1.54 x 10⁻¹³ M] = 12.81.

4 0

3 years ago

Determine the grams of protein in one cup of soup that has 140 kcal with 8 g of carbohydrate and 2 g of fat.

irina [24]

There are 22.5 grams of protein in one cup of soup that has 140 kcal with 8 g of carbohydrate and 2 g of fat.

<h3>What is the mass of a substance?</h3>

The mass of a substance is the quantity of the substance that is being measured in grams or kilograms.

To determine the energy from the 8g of carbohydrate, we have:

= 8g × 4 kcal/g (the corresponding calories of food type)

= 32 kcal

The energy from 2g of fat = 2g × 9 kcal/g

= 18 kcal

The energy from protein is calculated as:

= 140 kcal - 32 kcal - 18 kcal

= 90 kcal

The required mass of the protein in grams is:

$\mathbf{= 90 \ kcal \times \dfrac{1}{4 \ kcal }}$

= 22.5 grams

Therefore, we can conclude that there are 22.5 grams of protein in one cup of soup.

Learn more about the mass of a substance here:

brainly.com/question/837939

#SPJ1

7 0

1 year ago

In which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correctly?

Maksim231197 [3]

In, 49 protons, 49 electrons

3 0

3 years ago

How many moles of carbon are in 5.2 moles of C7H18?

bulgar [2K]

There is a shortcut to this Chem question. simply look at this problem as if it were a cooking recipe. you have 7 parts Carbon and 18 Parts Hydrogen for a total of 25 parts. Simply divide 5.2 by 25 then multiply by 7 to get your answer.
(5.2/ 25) 7 = 1.456 moles

8 0

3 years ago

Read 2 more answers