C1- Fundemental ideas

Question 1

What are the names and numbers of the particles in an atom of sodium (atomic number 11, mass number 23)?

Answer 1

11 protons, 11 electrons , 12 neutrons

Question 2

Sort these substances into elements and compounds:

Ca,CH4, H2 HCI, MgO,O2,SO2

Answer 2

Elements: Ca,H2,Ne,O2
Compounds: CH4 HCI MgO SO2

Question 3

What determines the order of the elements in the periodic table?

Answer 3

In order of atomic number ( proton numbers)

Question 4

Explain why boron and aluminum are both in the same group in the periodic table?

Answer 4

Both have 3 (same number of) electrons in their highest energy level ( outer shell).

Question 5

Name the type of bonds in each of these compounds:

CaO, C2 H6, KCI, LiCI, MgCI2 NH3 , NA2, O, PCI3

Answer 5

Ionic: CaO, KCI,LiCI, MgCI2, Na2 O
Covalent: C2 H6,NH3, PCI3

Question 6

Explain what happens to the atoms when a sodium atom reacts with a chlorine atom.

Answer 6

Sodium atom loses and an electron and becomes a sodium ion with a positive charge, chlorine atom gains an electron and becomes chlorine ion with a negative charge.

Question 7

The equation for a reaction of lead nitrate is:
Pb(NO3)2+ 2Ki -> 2KNO3+PBI2
A Write a word equation for this reaction
B Give the name and number of each type of atoms in the products.

Answer 7

A. lead nitrate + potassium iodide-> potassium nitrate+ lead iodide
B. two potassium atoms/ions, two nitrogen atoms, six oxygen atoms, one lead atom/ion, two iodine atoms/iodide ions

Question 8

Calcium carbonate decomposes when heated to produce calcium oxide and carbon dioxide. 20.0g of calcium carbonate produced 11.2g of calcium oxide. What mass of carbon dioxide would be produced?

Answer 8

8.8g

Question 9

Balance these symbol equations:
A. Ca+ O2 -> CaO
B.Na+ H2O-> NaoH+ H2
C. CH4+ O2-> Co2+H2O

Answer 9

A.2Ca+O2->2CaO
B. 2Na+2H2O-> 2NaOH+H2
C. CH4+2O2 ->CO2 +2H2O