The atomic structure of an unknown element is shown below.
What is the atomic number and mass number for the unknown element?
Atomic Number | Mass Number | |
A | 6 | 11 |
B | 5 | 11 |
C | 5 | 6 |
D | 6 | 10 |
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The atomic structure of an unknown element is shown below.
What is the atomic number and mass number for the unknown element?
Atomic Number | Mass Number | |
A | 6 | 11 |
B | 5 | 11 |
C | 5 | 6 |
D | 6 | 10 |
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Element Cu has two isotopes. Their mass numbers are 63 and 65.
Estimate the relative atomic mass of element Cu.
Below 63
Between 63.5 and 64
Between 64 and 64.5
Above 64.5
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Niels Bohr was one scientist who contributed to the development of the atomic model.
What was his discovery?
An atom is a ball of positive charge with electrons scattered throughout it
An atom is mainly empty space
Mass is concentrated at the centre of the atom called the nucleus
Electrons exist in shells and orbit the nucleus at specific distances
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Symbol equations always need to have the same number of atoms on both sides.
Which equation is not correctly balanced?
H2SO4 + 2NaOH → Na2SO4 + 2H2O
Ca(OH)2 + 2HCl → CaCl2 + 2H2O
4Na + O2 → 2Na2O
2Cu + HNO3 → 2Cu(NO3)2 + H2
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As the atomic model developed, protons, neutrons and electrons were discovered.
What is the correct order of discovery?
First | Second | Third | |
A | Proton | Neutron | Electron |
B | Proton | Electron | Neutron |
C | Electron | Proton | Neutron |
D | Electron | Neutron | Proton |
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