101.325 kPa = 760 mmHg.
So, 25.0 kPa is 187.515 mmHg
95.6 cal
are needed.
Explanation:
Use the following equation:
q
=
m
c
Δ
T
,
where:
q
is heat energy,
m
is mass,
c
is specific heat capacity, and
Δ
T
is the change in temperature.
Δ
T
=
T
final
−
T
initial
Known
m
=
125 g
c
Pb
=
0.130
J
g
⋅
∘
C
T
initial
=
17.5
∘
C
T
final
=
42.1
∘
C
Δ
T
=
42.1
∘
C
−
17.5
∘
C
=
24.6
∘
C
Unknown
q
Solution
Plug the known values into the equation and solve.
q
=
(
125
g
)
×
(
0.130
J
g
⋅
∘
C
)
×
(
24.6
∘
C
)
=
400. J
(rounded to three significant figures)
Convert Joules to calories
1 J
=
0.2389 cal
to four significant figures.
400
.
J
×
0.2389
cal
1
J
=
95.6 cal
(rounded to three significant figures)
95.6 cal
are needed.
Answer:
I'm pretty sure its stimulus
Answer:
no it is a ionic compound
Answer:
, zirconium-103.
Explanation:
In a nuclear reaction, both the mass number and atomic number will conserve.
Let
represent the unknown particle.
The mass number of a particle is the number on the upper-left corner. The atomic number of a particle is the number on its lower-left corner under the mass number. For example, for the particle
,
is the mass number while
while
is the atomic number.
Sum of mass numbers on the left-hand side of the equation:
.
Note that there are three neutrons on the right-hand side of the equation. Sum of mass numbers on the right-hand side:
.
Mass number conserves. As a result,
.
Solve this equation for
:
.
Among the five choices, the only particle with a mass number of 103 is
. Make sure that atomic number also conserves.