1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Triss [41]
3 years ago
5

True or False: A chemical reaction always happens when two substances are combined. (please help fast this is a test)

Physics
2 answers:
mina [271]3 years ago
8 0

Answer:probably false

Explanation:

Every time you mix two substances it doesn’t mean it’s going to have a reaction, they have to be two substances that don’t combine. I really hope this helps

Makovka662 [10]3 years ago
6 0

Answer:

no not always sometimes they react at all so false I hope I helped :)

You might be interested in
What is momentum equal to?
Setler [38]

Answer:

D

Explanation:

mass times velocity

hope this help

8 0
3 years ago
Graphs are representations of equations.<br> A. True<br> B. False
zhuklara [117]

Answer:

Hi there!

The answer is: A. True

6 0
3 years ago
Read 2 more answers
The molecular weight of oxygen gas (o2) is 32 while that of hydrogen gas (h2) is 2.
anzhelika [568]

use the formula: v^2=(3kT)/m

Where:

<em>v is the velocity of a molecule</em>

<em>k is the Boltzmann constant (1.38064852e-23 J/K)</em>

<em>T is the temperature of the molecule in the air</em>

<em>m is the mass of the molecule</em>

For an H2 molecule at 20.0°C (293 K):

v^2 = 3 × 1.38e-23 J/K × 293 K / (2.00 u × 1.66e-27 kg/u)

v^2 = 3.65e+6 m^2/s^2

v = 1.91e+3 m/s

For an O2 molecule at same temp.:

v^2 = 3 × 1.38e-23 J/K × 293 K / (32.00 u × 1.66e-27 kg/u)

v^2 = 2.28e+5 m^2/s^2

v = 478 m/s

Therefore, the ratio of H2:O2 velocities is:

1.91e+3 / 478 = 4.00

7 0
3 years ago
I need help please will mark brainliest
Valentin [98]

Answer:

200

Explanation:

20m/s*10sec=200

3 0
3 years ago
A gas has a variable volume.<br> True<br> False
nekit [7.7K]

Answer:

True

Explanation:

<em>Gas</em><em> </em><em>always</em><em> </em><em>live </em><em>in </em><em>free</em><em> </em><em>state </em><em>but </em><em>some </em><em>gas </em><em>is </em><em>not </em><em>.</em><em> </em><em>We </em><em>can </em><em>said</em><em> </em><em>that</em><em> </em><em>mostly</em><em> </em><em>gas </em><em>volume</em><em> </em><em>can </em><em>be </em><em>changeable </em><em>during</em><em> </em><em>disturbing</em><em> </em><em>by </em><em>environment </em><em>situation</em><em>.</em>

4 0
2 years ago
Other questions:
  • Is a sound wave mechanical or an electromagnetic wave
    13·1 answer
  • A suspension bridge with weight uniformly distributed along its length has twin towers that extend 90 meters above the road surf
    8·1 answer
  • This is a wave whose energy travels in the same direction as the energy being transferred.
    13·1 answer
  • Discuss two components that are essential to the functioning of the ecosystem.
    7·1 answer
  • A stone of density 5500 kg/m3 is submerged in water. If the volume of the stone is 0.25 m3, the mass of water it displaces is___
    11·1 answer
  • A car accelerates from rest to 27 m/s in 8 seconds. What is the acceleration of the car?
    13·1 answer
  • The 5.00-cm-long second hand on a watch rotates smoothly. What is its angular velocity?
    6·1 answer
  • Scientists have observed that the average sunspots have increased in the last 50 years. Which of these statements best describes
    7·2 answers
  • Two masses of 3 kg and 5 kg are connected by a light string that passes over a smooth polley as shown in the Figure.
    7·1 answer
  • LU LIU
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!