4: Inorganic Chemistry Flashcards
What are Group 1 elements known as?
Alkali metals.
How do Group 1 metals react with water?
They react vigorously, producing a metal hydroxide solution and hydrogen gas.
What is the general word equation for the reaction of sodium with water?
Sodium + Water → Sodium Hydroxide + Hydrogen.
What is the balanced symbol equation for sodium reacting with water?
2Na(s) + 2H₂O(l) → 2NaOH(aq) + H₂(g).
How does reactivity change down Group 1?
It increases
Why does reactivity increase down Group 1?
The outer electron is further from the nucleus, making it easier to lose.
What metal oxides do Group 1 metals form with oxygen?
Lithium forms lithium oxide (Li₂O), sodium forms sodium oxide (Na₂O) and sodium peroxide (Na₂O₂), potassium forms potassium peroxide (K₂O₂) and potassium superoxide (KO₂).
What are Group 7 elements called?
Halogens.
How do the colors and boiling points of halogens change down the group?
They become darker in color and have higher boiling points.
What are the states and colors of chlorine, bromine, and iodine at room temperature?
Chlorine: Green gas, Bromine: Red-brown liquid, Iodine: Dark grey solid (produces purple vapor when heated).
How does reactivity change down Group 7?
It decreases
Why does reactivity decrease down Group 7?
The outer shell is further from the nucleus, making it harder to attract an extra electron.
What type of ion do halogens form?
A 1- ion by gaining one electron.
What happens in a displacement reaction?
A more reactive element displaces a less reactive element from a compound.
What happens when chlorine is added to potassium iodide solution?
Chlorine displaces iodine, forming potassium chloride and iodine (turns solution brown).
What is the word equation for chlorine displacing iodine from potassium iodide?
Chlorine + Potassium Iodide → Potassium Chloride + Iodine.
What is oxidation in terms of electron transfer?
Loss of electrons.
What is reduction in terms of electron transfer?
Gain of electrons.
What are the main gases in Earth’s atmosphere and their percentages?
78% nitrogen, 21% oxygen, nearly 1% argon, 0.04% carbon dioxide.
How can the proportion of oxygen in air be measured using iron?
Iron reacts with oxygen to form rust, removing oxygen from the air, and the water level in a measuring cylinder rises to show the percentage of oxygen used.
How can phosphorus be used to measure oxygen in the air?
Phosphorus is burned in a closed system, reacting with oxygen to form phosphorus oxide, and the decrease in air volume is measured.
What are the products when magnesium burns in oxygen?
Magnesium oxide (MgO), forming a white powder.
What happens when hydrogen burns in oxygen?
It forms water (H₂O) and burns with an orange/yellow flame.
How is the presence of hydrogen tested?
A lit splint gives a ‘squeaky pop’ sound in the presence of hydrogen.
