Ask question

Ask question

All categories

adelina 88 [10]

3 years ago

9

Which of the following is true about chemical reactions. A. they are accompanied by changes in energy. B. they form new substanc

es with new properties. C. both A & B
D.neither A nor B

1 answer:

Ilia_Sergeevich [38]3 years ago

7 0

The correct answer should be option C. hope this helps

You might be interested in

PLEASE HELP ME ASAP: Some students are using samples of different substances for a lab investigation. They plan to observe the p

marin [14]

Answer: S,Fe,O2,Sr, and Al

Explanation: I saw it on quizlet

3 0

3 years ago

describe the" fear appeal" and how it's used in public messaging. Give an example or create your own public health message using

Vsevolod [243]

A good example is cigarretes they try to scare you into not smoking by telling you all of the downsides of smoking like lung cancer and i guess that would be fear appeal

7 0

3 years ago

Which statement correctly describes an atom of the element helium? A. An atom of helium has a full outer energy level and is the

Citrus2011 [14]

The correct description for an atom of helium would be option C. An atom of helium has its valence electrons in its first energy level, it wouldn't and can't satisfy the Octet rule as it only has 2 electrons, but with 2, it has a full shell, as the first energy level can hold only 2 electrons.

4 0

3 years ago

An example of a suspension is:<br> A. blood<br> B. gelatin<br> C. muddy water<br> D. milk

Shkiper50 [21]

ANSWER:A.blood

WHY: because it make the most sense and it seem right

Can I get brainly

3 0

3 years ago

29. A gas has a volume of 1.75 L at -23°C and 150.0 kPa.

arsen [322]

The answer for the following mention bellow.

<u><em>Therefore the final temperature of the gas is 260 k</em></u>

Explanation:

Given:

Initial pressure ( $P_{1}$ ) = 150.0 kPa

Final pressure ( $P_{2}$ ) = 210.0 kPa

Initial volume ( $V_{1}$ ) = 1.75 L

Final volume ( $V_{2}$ ) = 1.30 L

Initial temperature ( $T_{1}$ ) = -23°C = 250 k

To find:

Final temperature ( $T_{2}$ )

We know;

According to the ideal gas equation;

P × V = n × R ×T

where;

P represents the pressure of the gas

V represents the volume of the gas

n represents the no of moles of the gas

R represents the universal gas constant

T represents the temperature of the gas

We know;

$\frac{P*V}{T}$ = constant

$\frac{P_{1} }{P_{2} }$ × $\frac{V_{1} }{V_{2} }$ = $\frac{T_{1} }{T_{2} }$

Where;

( $P_{1}$ ) represents the initial pressure of the gas

( $P_{2}$ ) represents the final pressure of the gas

( $V_{1}$ ) represents the initial volume of the gas

( $V_{2}$ ) represents the final volume of the gas

( $T_{1}$ ) represents the initial temperature of the gas

( $T_{2}$ ) represents the final temperature of the gas

So;

$\frac{150 * 1.75}{210 * 1.30}$ = $\frac{260}{T_{2} }$

( $T_{2}$ ) =260 k

<u><em>Therefore the final temperature of the gas is 260 k</em></u>

<u><em></em></u>

3 0

3 years ago