C1: Quiz 12 – Answers
1) The alkali metals
2)
a) 1 electron in their outermost electron shell
b) They want to lose 1 electron
c) They become positively charged by 1 (1+ ion)
3) The reactivities increase as we go down the group 1 column because the single electron that a lower down group 1 element wants to lose is on an electron shell that is further away from the positively charged nucleus. This means that there is a weaker force of attraction between the positively charged nucleus and the electron that further down group 1 elements are trying to lose. This weaker force of attraction means that less energy is required to remove the electron on the outmost shell of a further down group 1 element, which results in the reactivities increasing as we go down the group 1 column
4) Very reactive
5)
a) sodium + oxygen –> sodium oxide
b) Na2O
c) 4 Na + O2 –> 2 Na2O
6)
a) lithium + water –> lithium hydroxide + hydrogen
b) 2 Li + 2 H2O –> 2 LiOH + H2
c) an alkali
d) Hold a lit splint to the gas. If hydrogen is present, we will hear a squeaky pop
7)
a) potassium + chlorine –> potassium chloride
b) 2 K + Cl2 –> 2 KCl
8)
Word: sodium + water –> sodium hydroxide + hydrogen
Symbol: 2 Na + 2 H2O –> 2 NaOH + H2
9)
Word: lithium + fluorine –> lithium fluoride
Symbol: 2 Li + F2 –> 2 LiF
10)
a) decrease
b) increase
c) increase
11)
a) Sodium oxide (Na2O) and sodium peroxide (Na2O2)
b) Potassium peroxide (K2O2) and potassium superoxide (KO2)
1) What is another name for the group 1 elements?
2)
a) How many electrons do the group 1 elements have in their outermost electron shell?
b) Do the group 1 elements want to gain or lose electron(s), and how many electrons do they want to gain or lose?
c) When they gain or lose electron(s), do they become positively or negatively charged?
3) As we go down the group 1 elements in the periodic table, do they become more or less reactive? Explain your answer.
4) In comparison to other elements in the periodic table, would you say that the group 1 elements are very reactive or not very reactive?
5) Sodium reacts with oxygen to form sodium oxide.
a) Write the word equation for this reaction.
b) What is the chemical formula for sodium oxide?
c) Write the balanced symbol equation for this reaction.
6) Lithium reacts with water to form lithium hydroxide and hydrogen.
a) Write the word equation for this reaction.
b) Write the balanced symbol equation for this reaction.
c) Will the solution of lithium hydroxide be an acid, an alkali or neutral?
d) What is the test for hydrogen gas?
7) Potassium reacts with chlorine to form potassium chloride.
a) Write the word equation for this reaction.
b) Write the balanced symbol equation for this reaction.
8) Write the word and balanced symbol equation for sodium reacting with water.
9) Write the word and balanced symbol equation for lithium reacting with fluorine.
10) Answer the following sub questions with either increase or decrease.
a) As we go down the group 1 elements, the melting and boiling points _________
b) As we go down the group 1 elements, the densities _________
c) As we go down the group 1 elements, the reactivities _________
11) Sometimes when the group 1 metal react with oxygen, multiple oxides of the group 1 metal are produced.
a) What are the two oxides produced from sodium? Give the chemical formulas as well.
b) What are the two oxides produced from potassium? Give the chemical formulas as well.