Answer:
c = 0.07 j/g.k
Explanation:
Given data:
Mass of sample = 35 g
Heat absorbed = 48 j
Initial temperature = 293 K
Final temperature = 313 K
Specific heat of substance = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = Final temperature - initial temperature
ΔT = 313 k - 293 K
ΔT = 20 k
Now we will put the values in formula.
48 j = 35 g × c× 20 k
48 j = 700 g.k ×c
c = 48 j/700 g.k
c = 0.07 j/g.k
C = 0.11 mol
V = 5.65 L
n = ???
n = C*V
n = 0.11 * 5.65
n = 0.622 mols
1 mol of CaCl2 = 40 + 2*35.5 = 111 grams
0.622 mol = x
x = 111 * 0.622
x = 69.0 grams CaCl2
<h3>1. <u>Answer;</u></h3>
a. the strong nuclear force is much greater than the electric force.
<h3><u>Explanation</u>;</h3>
- <em><u>For an atom to be stable it means it has enough amount of binding energy to hold its nucleus together permanently. </u></em>
- Therefore, <em><u>an unstable atom lacks enough amount of binding energy to hold its nucleus permanently and thus undergoes decay to achieve stability. Unstable atoms are therefore referred to being radioactive.</u></em>
-
Small atoms are stable; <u>this is because they have equal number of protons and neutrons and thus the protons and neutrons fill up energy levels while maximizing the strong force binding the nucleus together. </u>
<h3>9.<u> Answer;</u></h3>
b. change into a different element altogether.
Uranium-238 undergoes alpha decay. Therefore, uranium-238 will <em><u>change into a different element altogether</u></em>.
<h3><u>
Explanation;</u></h3>
- Unstable atoms undergo radioactive decay in order to achieve stability of their nucleus.
- <em><u>Uranium-238 is an example of such atom, which may undergo decay to achieve stability.</u></em>
- <em><u>Alpha decay is one of the types of decays,</u></em> others being beta decay and gamma decay. <em><u>In alpha decay the radioactive isotope undergoes decay such that its mass number is decreased by four and its atomic number is decreased by two.</u></em>
-
Therefore, <em><u>Uranium-238 undergoes alpha decay to form a different element whose mass number is 234 and atomic number is 90, known as thorium-234. </u></em>
90% of energy is lost. only 10% is left.
therefore the answer is B. 90%