All categories

3 years ago

Which of the following is the correct definition of convection?

Chemistry

2 answers:

Paraphin [41]3 years ago

8 0

Answer:

A: The transfer of heat by currents.

Explanation:

Convection is the transfer of heat by currents, typically within a liquid or a gas. When heat is transferred by convection, matter flows.

kvv77 [185]3 years ago

3 0

Answer: A. the transfer of heat by currents

Explanation: There are three modes of heat transfer:

1) Conduction: This type of heat transfer happens when there is direct contact between the two object. Example: heating a pan on stove.

2) Convection: This type of heat transfer happens when there is a movement of fluid (liquid or gas) due to the movement of hot layers to the top and cold layers to the bottom which leads to convection currents. Example: Heating of swimming pool.

3) Radiation: This type of heat transfer happens when there is direct transfer of energy through space. Example: Heating of earth's surface.

B. The transmission of heat across matter is conduction.

C. The electromagnetic radiation from the surface of an object which is due to the object's temperature is radiation.

D. The transmission of heat across empty space is radiation.

You might be interested in

WILL GIVE BRAINIEST IF HELP Which of these is a compound

NikAS [45]

b the awnser is b its a compound of carbon C and 2 oxygon atoms O sub 2

5 0

3 years ago

The process by which wind removes surface materials is called what?

skelet666 [1.2K]

The process by which wind removes surface materials is called abrasion.

5 0

3 years ago

According to observations, the overall chemical composition of our solar system and other similar star systems is approximately

jonny [76]

Answer:A

Explanation:

The solar system consist of the sun, the planets, stars and other objects. The chemical composition of the Sun consist mainly of Hydrogen and helium.

The sun is the largest object in the Solar system, it comprises nearly all the matter in the Solar System, Also the largest planet after the Sun are Jupiter and Saturn are giant planets forming almost the remaining matter of the solar system.

Like the Sun, the mass of Jupiter and Saturn are composed of roughly 98% hydrogen and helium with 2% of all the other elements combined.

3 0

3 years ago

Give the result of the following mathematical operations to the correct number of significant figures. 5.659 * (3.496 - 2.814) =

shtirl [24]

Answer:

The result is 3.859 in which we use four significant figures.

Explanation:

We start by solving the mathematical operation :

$5.659.(3.496-2.814)=5.659(0.682)=3.859438$

The result for the operation is 3.859438 but the numbers in the operation are given with four significant figures and that is why we are going to use four significant figures to express the result

To express 3.859438 with four significant figures we use the first four digits that appear from left to right starting by the first digit that is different to zero

In this case : 3.859 will be the result with four significant figures.

We also use a rule that says : To decide if the last significant figure remains the same we look for the value of the digit at its right.

If that number is greater than or equal to 5 ⇒ we sum one to the last significant figure

For example 3.859738 = 3.860 with four significant figures because the ''7'' is greater that 5

If that number is less than 5 ⇒ the last significant figure remains the same

In our case : 3.859438 = 3.859 because ''4'' is less than ''5''

7 0

3 years ago

What is the molarity of a solution prepared by dissolving 54.3 g of Calcium nitrate

Ostrovityanka [42]

Answer: 40 + 2x14 + 6x16 = 164g/mole

54.3g x [1mole / 164g] = 0.331moles

355mL x 1L / 1000mL = 0.355L

molarity = 0.331moles / 0.355L =

Explanation:

5 0

2 years ago