The whole Activity , poem and paragraph is missing in the question.
Answer:
(1) Liquid A
(2) Solid A
Explanation:
Using this part of the given poem
Substances and mixtures behave differently,
During boiling and melting most especially
Boiling point of substance is fixed while mixture is not
Substance melts completely but mixture does not
The boiling point of the Pure substance remain fixed after reaching its boiling point this is shown by Liquid A
Solid A is melting completely so Solid A is a pure substance.
Answer:
Negative sign says that release of heat.
Explanation:
The expression for the calculation of the heat released or absorbed of a process is shown below as:-
Where,
is the heat released or absorbed
m is the mass
C is the specific heat capacity
is the temperature change
Thus, given that:-
Mass = 25.2 g
Specific heat = 0.444 J/g°C
So,
Negative sign says that release of heat.
To find average atomic mass you multiply the mass of each isotope by its percentage, and then add the values up.
35 * 0.90 + 37 * 0.08 + 38 * 0.02 = 35.22
Average atomic mass closest to 35.22 amu.
Answer:
Speed = frequency x wavelength 50 cm/s = Freq x 10cm
Explanation:
1. Answer is ₉₂²³⁵U<span>
<span>Since this is an alpha emission the atomic number
of the daughter nucleus decreases by 2 while mass number decreases by 4 compared to
parent atom. Since parent atom has 94 as atomic number the daughter atom should
have </span>94 - 2 = 92 as atomic number<span> <span>and </span></span>239 - 4 = 235 as mass
number. <span>
</span></span>₉₄²³⁹Pu → ₂⁴He + ₉₂²³⁵U<span>
2. </span><span>Answer is </span>₉₁²³⁴Pa<span>
</span><span>Since this is a beta emission, a neutron is
converted into a proton while emitting an electron. Hence atomic number
increases by 1 compared to mass number but mass number remains as same. Hence,
the </span>atomic number of the
daughter atom<span> <span>should be </span></span>90 + 1 = 91<span> <span>which belongs to </span></span>Pa<span>. But the </span>mass number is same
as 234.<span>
</span>₉₀²³⁴Th → ₋₁⁰e + ₉₁²³⁴Pa<span>
</span><span>
3.<span> <span>Answer is </span></span></span>₈¹⁸O<span>
</span><span>Since this is a positron emission, a proton is converted into a neutron
while emitting an positron. Hence atomic number decreases by 1 compared to mass
number but mass number remains as same. Hence, the </span>atomic number of the
daughter atom<span> should be </span>9- 1
= 8 <span>which belong to </span>O<span>. But the </span>mass
number is same as 18.<span>
</span>₉¹⁸F → ₊₁⁰e + ₈¹⁸O<span>
4. </span>Answer is ₈₀²⁰¹Hg<span>
</span><span>This is an </span><span>electron capture
decay. </span>A<span> proton is converted into a neutron by emitting
a gamma ray. In this process </span>mass number remains
as same<span> <span>as parent atom which is </span></span>201<span>, but the </span>atomic number is
decreased by 1<span> <span>than parent atom. Hence atomic number of
daughter nucleus is 81 -1 = </span></span>80 <span>which belongs to </span>Hg.<span>
</span><span>
</span>₈₁²⁰¹Tl + ₋₁⁰e → ₀⁰γ + ₈₀<span>²⁰¹Hg</span>
