of electrons 2) ) ) )

Transcription

1 1 st exam the 2 nd term for 2 nd ESO F Name: Date: 1. Complete the following table. Each row is a different atom: Atom protons neutrons 1) electrons Charge Anion, cation or neutral atom? Atomic number (Z) Mass number (A) 2) ) ) ) ) (2.4 points) 2. Knowing that the atoms in exercise 1 are: 1) Scandium, whose symbol is Sc 2) Hafnium, whose symbol is Hf 3) Rhodium, whose symbol is Rh 4) Bromine, whose symbol is Br 5) Barium, whose symbol is Ba 6) Sodium, whose symbol is Na Write these atoms with the same nomenclature as atoms in exercise 3. 1) 4) 2) 5) 3) 6) (0.6 points)

2 3. For the following atoms, write their number protons, their number neutrons, their number electrons, their charge, their atomic number (Z) and their mass number (A). a) b) c) d) e) (2.5 points) 4. For the following atoms, say their number protons, their number neutrons, their number electrons, their charge, their atomic number (Z) and their mass number (A). a) b) c)

3 d) (2 points) 5. In exercise 4, from atoms a) to d), are there any isotopes? If the answer is yes, which ones? How do you know? (0.5 points) 6. Write the four statements Dalton s atomic theory. (1 point) 7. Write if the following compounds are molecules or crystals: (0.4 points)

4 8. Place atoms 1), 4) and 6) from exercise 2 in the following blank periodic table. Say for each one their group and period: (0.6 points)

5 1 st exam the 2 nd term for 2 nd ESO F (answers) Name: Date: 1. Complete the following table. Each row is a different atom: Atom protons neutrons electrons Charge Anion, cation or neutral atom? Atomic number (Z) 1) cation Mass number (A) 2) anion ) neutral atom ) anion ) cation ) cation (2.4 points) 2. Knowing that the atoms in exercise 1 are: 1) Scandium, whose symbol is Sc 2) Hafnium, whose symbol is Hf 3) Rhodium, whose symbol is Rh 4) Bromine, whose symbol is Br 5) Barium, whose symbol is Ba 6) Sodium, whose symbol is Na Write these atoms with the same nomenclature as atoms in exercise 3. 1) 4) 2) 5) 3) 6) (0.6 points)

6 3. For the following atoms, write their number protons, their number neutrons, their number electrons, their charge, their atomic number (Z) and their mass number (A). a) b) c) d) e) a) Z=31, A=69, charge=0, protons=31, neutrons=38, electrons=31 b) Z=3, A=7, charge=+1, protons=3, neutrons=4, electrons=2 c) Z=85, A=210, charge=-1, protons=85, neutrons=125, electrons=86 d) Z=23, A=51, charge=-2, protons=23, neutrons=28, electrons=25 e) Z=14, A=28, charge=+4, protons=14, neutrons=14, electrons=10 (2.5 points) 4. For the following atoms, say their number protons, their number neutrons, their number electrons, their charge, their atomic number (Z) and their mass number (A). a) protons=2, neutrons=1, electrons=1, charge=+1, Z=2, A=3 You can check on your periodic table that it is.

7 b) protons=6, neutrons=8, electrons=8, charge=-2, Z=6, A=14 You can check on your periodic table that it is. c) protons=4, neutrons=6, electrons=5, charge=-1, Z=4, A=10 You can check on your periodic table that it is. d) protons=6, neutrons=6, electrons=6, charge=0, Z=6, A=12 You can check on your periodic table that it is. (2 points)

8 5. In exercise 4, from atoms a) to d), are there any isotopes? If the answer is yes, which ones? How do you know? (0.5 points) Yes, b) and d) are isotopes because they have the same atomic number (Z) and different mass number (A) (they have the same number protons and different number neutrons). 6. Write the four statements Dalton s atomic theory. (1 point) Matter is formed indivisible particles called atoms. Each chemical element is made up a different type atom, each with its own properties. Elements (simple substances) are made bonds between identical atoms. In contrast, different types atoms make compounds when bonded. A chemical change, unlike a physical change, involves re-ordering the atoms in a substance. These different bonds create new substances. 7. Write if the following compounds are molecules or crystals: (0.4 points)

9 8. Place atoms 1), 4) and 6) from exercise 2 in the following blank periodic table. Say for each one their group and period: (0.6 points) Na: group 1, period 3 Sc: group 3, period 4 Br: group 17, period 4