All categories

4 years ago

Musiclover10045 HELPPPPPPPPPPPPPPP

Chemistry

2 answers:

leonid [27]4 years ago

5 0

Answer:

1 ) A change in color of substance

2) The given statement is false.

3) A burning of candle is a chemical change.

Explanation:

A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions.

Example : Melting of ice

Physical property is defined as the property which can be measured and whose value describes the state of physical system. For Example: State, density etc.

A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions.

Example: Corrosion of iron called as rusting.

Chemical property is defined as the property of a substance which is observed during a reaction where the chemical composition identity of the substance gets changed.

Precipitate is solid substance formed from the mixing of two different solutions.

Zinaida [17]4 years ago

4 0

1. a change in the color of a substance

2. False, a precipitate is a solid not a gas

3. a burning candle

You might be interested in

Surface temperatures on Venus, the hottest planet in our solar system, can reach 755K. Express this temperature in degrees Fahre

dmitriy555 [2]

Answer:

about 900 degree Fahrenheit

Explanation:

7 0

3 years ago

Which of the following could result from a substance that undergoes a physical change?

Semmy [17]

Answer:

Its shape is altered.

Explanation:

For example, an ice cube melting into a puddle.

5 0

3 years ago

What is the color of the sky? (Wrong answers only)

Pavlova-9 [17]

Answer:

Red

Explanation:

5 0

4 years ago

Read 2 more answers

A red light source emits light of a certain frequency. A violet light source emits light that has double the frequency of the re

zloy xaker [14]

The wavelength of red light is double the wavelength of violet light.

<h3>Explanation:</h3>

Let $n_R$ = Frequency of red light source

Let $n_V$ = Frequency of violet light source

Let λR = Wavelength of red light source

Let λV = Wavelength of violet light source

Given: Frequency of violet light is two times (double) the frequency of red light.

Therefore $n_V = 2\times n_R$ ........................(1)

The relation between speed of light (c), frequency (n) and wavelength (λ) is given by

c = nλ

<em>Frequency is inversely proportional to λ.</em>

The speed of light remains constant for both light sources = c = 3 × 10⁸ m/s²

For red light source: $c = n_R\times$ λR ........................(2)

For violet light source: $c = n_V\times$ λV ..................(3)

Equating (2) and (3), we get

$c= n_R\times$ λR = $n_V \times$ λV

From (1)

$n_R\times$ λR = $2\times n_R\times$ λV

λR = 2 × λV

Therefore, wavelength of red light is two times the wavelength of violet light.

4 0

3 years ago

Read 2 more answers

Complete the table:

Stells [14]

Answer:

Mass solution = 28.65 g

Mass percent = 9.14 %

Mass solute = 1.95 g

Mass solution = 48.75 g

Mass solvent = 24.52 g

Mass percent = 6.41 %

Mass solution = 476.8 g

Mass solvent =450.1 g

Explanation:

Hello,

In this case, we define the mass percent as:

$\%m/m=\frac{m_{solute}}{m_{solute}+m_{solution}} *100\%$

Wherein we use the mass of the solute and the mass of the solvent in order to compute it, thus, for each case we have:

Mass solution: 2.65 g + 26.0 g = 28.65 g

Mass percent: 2.62 g / (2.65 g + 26.0 g) x 100% = 9.14 %

Mass solute: 4.0 % x 46.8 g / (1 - 4.0 %) = 1.95 g

Mass solution: 1.95 g + 46.8 g = 48.75 g

Mass solvent: 26.2 g - 1.68 g = 24.52 g

Mass percent: 1.68 g / (1.68 g + 24.52 g) x 100% = 6.41 %

Mass solution: 26.7 g / 5.6 % = 476.8 g

Mass solvent: 476.8 g - 26.7 g =450.1 g

Best regards.

7 0

3 years ago