Answer: To be able to not forget what have they done when they want to re-do it.
to make it easier for the next person to re-do the experiment.
Explanation:
the description of the procedure ensures that when the experiment becomes of a success,specific steps are recorded for improvement of the experiment if maybe the experiment can be done at a short space of time.
Answer:
2KBr + MgF₂ –> 2KF + MgBr₂
The coefficients are: 2, 1, 2, 1
Explanation:
KBr + MgF₂ –> KF + MgBr₂
The above equation can be balance as illustrated below:
KBr + MgF₂ –> KF + MgBr₂
There are 2 atoms of F on the left side and 1 atom on the right. It can be balance by writing 2 before KF as shown below:
KBr + MgF₂ –> 2KF + MgBr₂
There 2 atoms of K on the right side and 1 atom on the left side. It can be balance by writing 2 before KBr as shown below:
2KBr + MgF₂ –> 2KF + MgBr₂
Now, the equation is balanced.
The coefficients are: 2, 1, 2, 1
Answer:
166,600J
Explanation:
Kinetic energy (K.E), which is the energy due to motion of a body, can be calculated by using the formula;
K.E = 1/2 × m × v²
Where;
K.E = kinetic energy (joules)
m = mass of body (kg)
v = speed or velocity (m/s)
According to this question, the mass of the roller coaster is 833.0 kg while its velocity/speed is 20.0m/s.
K.E = 1/2 × 833 × 20²
K.E = 1/2 × 833 × 400
K.E = 1/2 × 333200
K.E = 166,600
Therefore, the kinetic energy of the roller coaster car is 166,600J.
The term Big Bang defines that the Universe has expanded from the ancient hot and thick primary situation at some fixed time in the past.
Big Bang theory refers to the origin of the Universe. In the beginning, universe is very heavy and small hot ball of matter. It was a point no bigger than the head of a pin when all the things squished with each other and universe is expanded with huge explosion of energy. Due to expansion, it is cooled and results in the formation of Stars and galaxies. After sometime, atoms formed like helium and hydrogen.
Thus, statement (1), (3) and (4) is correct whereas statement (2) and (5) is incorrect.
Answer:
The volume of 5.0 g CO 2 is 2.6 L CO 2 at STP
Explanation:
STP
STP is currently
0
∘
C
or
273.15 K
, which are equal, though the Kelvin temperature scale is used for gas laws; and pressure is
10
5
.
Pascals (Pa)
, but most people use
100 kPa
, which is equal to
10
5
.
Pa
.
You will use the ideal gas law to answer this question. Its formula is:
P
V
=
n
R
T
,
where
P
is pressure,
V
is volume,
n
is moles,
R
is a gas constant, and
T
is temperature in Kelvins.
Determine moles
You may have noticed that the equation requires moles
(
n
)
, but you have been given the mass of
CO
2
. To determine moles, you multiply the given mass by the inverse of the molar mass of
CO
2
, which is
44.009 g/mol
.
5.0
g CO
2
×
1
mol CO
2
44.009
g CO
2
=
0.1136 mol CO
2
Organize your data
.
Given/Known
P
=
100 kPa
n
=
0.1136 mol
R
=
8.3145 L kPa K
−
1
mol
−
1
https://en.wikipedia.org/wiki/Gas_constant
T
=
273.15 K
Unknown:
V
Solve for volume using the ideal gas law.
Rearrange the formula to isolate
V
. Insert your data into the equation and solve.
V
=
n
R
T
P
V
=
0.1136
mol
×
8.3145
.
L
kPa
K
−
1
mol
−
1
×
273.15
K
100
kPa
=
2.6 L CO
2
rounded to two significant figures due to
5.0 g
Answer link
Doc048
May 18, 2017
I got 2.55 Liters
Explanation:
1 mole of any gas at STP = 22.4 Liters
5
g
C
O
2
(
g
)
=
5
g
44
(
g
mole
)
=
0.114
mole
C
O
2
(
g
)
Volume of 0.114 mole
C
O
2
(
g
)
= (0.114 mole)(22.4 L/mole) = 2.55 Liters
C
O
2
(g) at STP