Exam 1 V2: Chem 110 | Physical
Chemistry | Latest Update
| Questions and verified Answers |
100% Correct (Grade A)
The periodic chart is a tool that chemistry students (and chemists) use to find elements and their
properties. Use a periodic chart to find the elements with the following atomic umbers and enter
the element name: 4 __, 21 __, 53 __, and 102 __.
4-Be, 21-Sc, 53-I, and 102-No.
How many electrons, protons and neutrons are in these elements?
Sodium - 11; 11; 12
Barium - 56; 56; 81
Cobalt - 27; 27; 32
Tin - 50; 50; 69
Boron - 5; 5; 6
Silicon - 14; 14; 14
Nitrogen - 7; 7; 7
Fluorine - 9; 9; 10
Helium has a matching number of protons and neutrons. What atomic mass (in units of amu)
would you predict for an element that has an atomic number of 5, if you assume an equal number
of protons and neutrons? Please only enter the numeric value, do not include units. Enter your
answer with 2 decimal places.
10.08
, Exam 1 V2: Chem 110 | Physical
Chemistry | Latest Update
| Questions and verified Answers |
100% Correct (Grade A)
Use the atomic mass in the periodic table to determine which of the stable isotopes in each set is
the predominant one in nature.
Li-6; Li-7 = Li-7
C-12; C-13 = C-12
N-14; N-15 = N-14
How many significant figures are in each of these numbers?
0.00142 = 3
0.1021 =4
5.02 = 3
33.020 = 5
100.02 = 5
10.00 = 4
500 = 1
73600 = 3
173600.1 = 7
802000 = 3
Enter the number of electrons, protons and neutrons in these isotopes respectively:
Chemistry | Latest Update
| Questions and verified Answers |
100% Correct (Grade A)
The periodic chart is a tool that chemistry students (and chemists) use to find elements and their
properties. Use a periodic chart to find the elements with the following atomic umbers and enter
the element name: 4 __, 21 __, 53 __, and 102 __.
4-Be, 21-Sc, 53-I, and 102-No.
How many electrons, protons and neutrons are in these elements?
Sodium - 11; 11; 12
Barium - 56; 56; 81
Cobalt - 27; 27; 32
Tin - 50; 50; 69
Boron - 5; 5; 6
Silicon - 14; 14; 14
Nitrogen - 7; 7; 7
Fluorine - 9; 9; 10
Helium has a matching number of protons and neutrons. What atomic mass (in units of amu)
would you predict for an element that has an atomic number of 5, if you assume an equal number
of protons and neutrons? Please only enter the numeric value, do not include units. Enter your
answer with 2 decimal places.
10.08
, Exam 1 V2: Chem 110 | Physical
Chemistry | Latest Update
| Questions and verified Answers |
100% Correct (Grade A)
Use the atomic mass in the periodic table to determine which of the stable isotopes in each set is
the predominant one in nature.
Li-6; Li-7 = Li-7
C-12; C-13 = C-12
N-14; N-15 = N-14
How many significant figures are in each of these numbers?
0.00142 = 3
0.1021 =4
5.02 = 3
33.020 = 5
100.02 = 5
10.00 = 4
500 = 1
73600 = 3
173600.1 = 7
802000 = 3
Enter the number of electrons, protons and neutrons in these isotopes respectively:
