Question 4:
Figure 2 shows the nucleus charges of the atoms of elements X, Y and Z.
(a) State the subatomic particle that provides the charges in the atoms of the elements.
(b) State the other subatomic particle found in the nucleus of the atoms.
(c) Write the electron arrangement of the atoms for elements X, Y and Z.
(d) Atom Z contains 14 neutrons. Calculate the nucleon number of atom Z.
Answer:
(a) Proton
(b) Neutron
(c)
X: 2.1
Y: 2.7
Z: 2.8.3
(d)
Nucleon number of Z atom
= 13 + 14
= 27
Figure 2 shows the nucleus charges of the atoms of elements X, Y and Z.
(a) State the subatomic particle that provides the charges in the atoms of the elements.
(b) State the other subatomic particle found in the nucleus of the atoms.
(c) Write the electron arrangement of the atoms for elements X, Y and Z.
(d) Atom Z contains 14 neutrons. Calculate the nucleon number of atom Z.
Answer:
(a) Proton
(b) Neutron
(c)
X: 2.1
Y: 2.7
Z: 2.8.3
(d)
Nucleon number of Z atom
= 13 + 14
= 27
Question 5:
Figure 3 shows the information on boron. Boron has two isotopes, namely isotope 11B and isotope yB.
Based on the information given, calculate the nucleon number of isotope yB.
Answer:
y = nucleon number of yB isotope
$$ \begin{aligned} &\text { Relative atomic mass of boron }=10.81\\ &\begin{aligned} \frac{(80.0 \times 11)+(20.0 \times y)}{100} & =10.81 \\ 880+20 y & =1081 \\ y & =\frac{1081-880}{20} \\ y & =10.05 \end{aligned} \end{aligned} $$
Hence, the nucleon number of yB isotope = 10
Figure 3 shows the information on boron. Boron has two isotopes, namely isotope 11B and isotope yB.
Based on the information given, calculate the nucleon number of isotope yB.
Answer:
y = nucleon number of yB isotope
$$ \begin{aligned} &\text { Relative atomic mass of boron }=10.81\\ &\begin{aligned} \frac{(80.0 \times 11)+(20.0 \times y)}{100} & =10.81 \\ 880+20 y & =1081 \\ y & =\frac{1081-880}{20} \\ y & =10.05 \end{aligned} \end{aligned} $$
Hence, the nucleon number of yB isotope = 10
Question 6:
Figure 4 shows the standard representation of a platinum atom. A platinum ion contains 74 electrons and has a nucleon number of 195.
(a) What are the number of protons and neutrons in the platinum ion?
(b) What is the charge of the platinum ion?
Answer:
(a)
Number of protons = 78
Number of neutrons
= 195 – 78
= 117
(b)
Charge of platinum ion
= 78 – 74
= +4
Figure 4 shows the standard representation of a platinum atom. A platinum ion contains 74 electrons and has a nucleon number of 195.
(a) What are the number of protons and neutrons in the platinum ion?
(b) What is the charge of the platinum ion?
Answer:
(a)
Number of protons = 78
Number of neutrons
= 195 – 78
= 117
(b)
Charge of platinum ion
= 78 – 74
= +4
Question 7:
Justify the use of iodine-131 in the treatment for hyperthyroidism.
Answer:
(Suitable student’s answer)
Reasonable
– The dosage of iodine-131 that is given for treatment is small
– The thyroid gland that secretes excess hormone can be destroyed
– Problems caused by hyperthyroidism such as rapid pulse rate, excessive sweating, drastic weight loss and others can be overcome
Unreasonable
– The thyroid gland is destroyed when undergoing hyperthyroidism treatment using iodine-131
– The thyroid gland plays an important role in producing hormones for body metabolism
– The patient needs to take thyroid pills after undergoing hyperthyroidism treatment
Justify the use of iodine-131 in the treatment for hyperthyroidism.
Answer:
(Suitable student’s answer)
Reasonable
– The dosage of iodine-131 that is given for treatment is small
– The thyroid gland that secretes excess hormone can be destroyed
– Problems caused by hyperthyroidism such as rapid pulse rate, excessive sweating, drastic weight loss and others can be overcome
Unreasonable
– The thyroid gland is destroyed when undergoing hyperthyroidism treatment using iodine-131
– The thyroid gland plays an important role in producing hormones for body metabolism
– The patient needs to take thyroid pills after undergoing hyperthyroidism treatment