False because when a substance changes from one state of matter to another it is a physical change no matter how many states of matter it skips
Answer:
The reaction begins and builds up heat. This heat causes the aluminum to melt and float on top of the liquid bromine. Wherever the two elements meet, sparks, heat, and light are given off.
Explanation:
The resulting pressure of the gas after decreasing the initial volume from 2 L to 1 L is 3 atm.
<h3>What is
Boyle's Law?</h3>
According to the Boyle's Law at constant temperature, pressure of the gas is inversely proportional to the volume of that gas.
For the given question we use the below equation is:
P₁V₁ = P₂V₂, where
P₁ = initial pressure of gas = 1.5 atm
V₁ = initial volume of gas = 2 L
P₂ = final pressure of gas = ?
V₂ = final volume of gas = 1 L
On putting all these values on the above equation, we get
P₂ = (1.5atm)(2L) / (1L) = 3 atm
Hence required pressure of the gas is 3 atm.
To know more about Boyle's Law, visit the below link:
brainly.com/question/469270
Answer:
d. white blood cells
Explanation:
It is the white blood cells that have the least tendency to cross the blood- brain barrier.
Blood- brain barrier is psychological barrier and restricts substances that circulate into the blood from crossing over the central nervous system.
Water, glucose as well as sodium ions can easily cross the barrier. As these are good for body supply energy to the brain.
Answer:
Correct option is
B
5 liters of CH
4
(g)NO
2
at STP
No. of molecules=
22.4
5
mol=
22.4
5
×N
A
molecules
A) 5ℊ of H
2
(g)
No. of moles=
2
5
mol=
2
5
×N
A
molecules
B) 5l of CH
4
(g)
No. of moles of CH
4
=
22.4
5
mol=
22.4
5
N
A
molecules
C) 5 mol of O
2
=5N
A
O
2
molecules
D) 5×10
23
molecules of CO
2
(g)
Molecules of 5l NO
2
(g) at STP=5l of CH
4
(g) molecules at STP
Therefore, option B is correct.
