January 2017 Chemistry Regents #1-5
Highlight to reveal answers and explanations
| |||
Questions | Answer | Links | Explanations |
1 Which statement describes the location of two types of subatomic particles in a helium atone (1) Protons and neutrons are located in the nucleus. (2) Protons and neutrons are located outside the nucleus. (3) Protons and electrons are located in the nucleus. (4) Protons and electrons are located outside the nucleus. | 1 | protons and neutrons are in the nucleus electrons are outside | |
2 An atom that contains six protons, six neutrons, and six electrons has a mass of approximately (1) 12 u (3) 18 u (2) 12 g (4) 18 g | 1 | p= 1 u n=1 u e= 0 u 6+6+0=12u | |
3 Which term identifies the most probable location of an electron in the wave-mechanical model of the atom? (l) anode (3) nucleus (2) orbital (4) cathode | 2 | electrons are found in orbitals | |
| |||
4 Which element has atoms in the ground state with the greatest number of valence electrons? (1) tin (3) arsenic (2) sulfur (4) fluorine | 4 | F 2-7 7 valence electrons (last # in e config) | |
5 Which group on the Periodic Table has two elements that exist as gases at STP? (1) Group 1 (3) Group 16 (2) Group 2 (4) Group 17 | 4 | G17 F2 and Cl2 are gases | |
|