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4 years ago

How is electromagnetic energy fromthe microwave transformed into heat energy

Chemistry

2 answers:

zysi [14]4 years ago

6 0

Answer:

First, the microwaves transmit kinetic energy to the water molecules of the food, heating the water molecules. Only, those that are not very deep into the food.

Second, the hot water molecules transmit heat by conduction to the other parts of the food.

Explanation:

1) Microwaves are a form of electromagnetic radiation. The same as any wave, they carry energy.

2) The wave length of microwaves are in the range of 0.001 mm to 1 m (shorter than radio waves and longer than infrared)

3) The microwaves of an oven, used to heat food, have a wave length aroun 12 cm.

4) The microwaves transmit energy to the water molecules in the food, by increasing the kinetic energy of water molecules. As result, the water molecules get hotter. Microwaves only penetrate about 1 cm inside the food (a potato for example) and from that the heat is transferred by conduction to the inner parts of the food.

Marizza181 [45]4 years ago

3 0

When light hits a white surface, rays are reflected. When light hits a black surface the light is changed to heat.

Infrared is electromagnetic energy. When it hits a material it causes the molecules to move faster which is showing more energy

Microwave energy is used to make food molecules hotter in the way explained above.

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Explain by means of why is reddish orange is observed when you add sodium chloride

Lemur [1.5K]

Answer:

because the orange is unripe

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3 years ago

How did Dalton describe the relationship between atoms and elements? An element is made up of one kind of atom. Atoms are made u

victus00 [196]

Answer: An element os made up of one kind of atom.

Explanation: Dalton's concept states that all atoms of an element is identical.

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3 years ago

Read 2 more answers

I need half reactions, for the following equation.

zhuklara [117]

Answer : Half reaction is defined as the reaction which will be either the oxidation or reduction reaction of particular species in a given redox reaction.

So as per the definition in the reaction of,

 $Ba + ZnSO_{4} ----\ \textgreater \ BaSO_{4} + Zn$

 $Ba_{(s)} + Zn ^{+2} + SO_{4}^{-2} = Ba^{+2} + SO_{4}^{-2} + Zn_{(s)}$

here on left and right side $SO_{4}^{-2}$ will get cancelled.

and we will get, $Ba_{(s)} + Zn ^{+2} = Ba^{+2} + Zn_{(s)}$

Here,
$Ba_{(s)} ----\ \textgreater \ Ba^{+2} - 2e^{-}$ ...this is oxidation reaction as Ba is getting reduced to $Ba^{+2}$ by losing 2 electrons.

whereas,on the other hand, $Zn ^{+2} ----\ \textgreater \ Zn_{(s)} + 2e ^{-}$ ...this is reduction reaction as $Zn ^{+2}$ is getting reduced to Zn by gaining 2 electrons.

8 0

3 years ago

Small quantities of oxygen can be prepared in the laboratory by heating potassium chlorate, KClO3(s).

pychu [463]

Answer:

26.110 grams of O2 produced.

Explanation:

Calculate the amount of moles in KClO3 by dividing the amount of grams given by the atomic weight of the substance.

To get the atomic weight: K = 39.098, Cl = 35.45, O = 15.999, and there are 3 molecules of Oxygen, so multiply 15.999 by three.

39.098 + 35.45 + (15.999 * 3) = 122.548.

66.7g / 122.548 atomic mass = 0.544 moles.

The ratio of moles of KClO3 to moles of O2 is 2 to 3.

$\frac{2}{3}$ = $\frac{0.544}{y}$

Cross multiply to get 1.632 = 2y. Y = 0.816, meaning 0.816 moles of O2 will be produced.

Convert this into grams by multiplying by the atomic weight of O2 (15.999 * 2 = 31.998).

0.816 * 31.998 = 26.110 grams of O2 produced.

3 0

3 years ago

6 How many moles are in a 321 g sample of magnesium?

Tatiana [17]

Answer:

13.4mol of Mg

Explanation:

Given parameters:

Mass of magnesium = 321g

Unknown:

Number of moles = ?

Solution:

The number of moles of a substance is given as;

Number of moles = $\frac{mass}{molar mass}$

Molar mass of Mg = 24g/mol

Insert the parameters and solve;

Number of moles = $\frac{321}{24}$ = 13.4mol of Mg

3 0

3 years ago