Period 3 Flashcards
State the element in period 3 that has the highest first ionisation energy.
Explain your answer.
Argon
Has the largest number protons and has the same number of sheilding
Which element forms an ionic oxide that reacts with strong alkalis?
Aluminium
Which is the formula of the main aluminium-containing species present when
aluminium oxide is added to an excess of water?
Al2O3(s)
Write an equation including state symbols for the reaction of sodium with water.
2Na(s) + 2H2O(l) —> 2NaOH(aq) + H2(g)
Why would a reaction between a big amount of sodium and a small amount of water be dangerous when reacting together
Temperature will go up or reactants can shoot out of the tube
Give an equation for the reaction between phosphorus(V) oxide with water
P4O10 +6H2O —> 4H3PO4
Suggest the PH for 4H3PO4
2
Explain in terms of crystal structure and bonding, why silicon (IV) oxide has a higher melting point than phosphorus(V) oxide.
SiO2 is giant covalent structure with strong covalent bonds that require a lot of energy to be broken.
P4O10 is a simple covalent molecule and van der waal forces between molecules break easily
Give the formula of a hydroxide of an element in period 3 used in medicine
MgOH2
Give the formula for the oxide
Give an equation for the reaction of the oxide with sulfuric acid
Al2O3
Al2O3 +3H2SO4 —> Al2(SO4)3 + 3H2O
Explain why the atomic radius decreases across Period 3, from sodium to chlorine
The number of protons increases and shielding is similar/ the same
The number of proton
What element in period 3 from sodium to argon has the highest second ionisation energy
Write an equation to show the process when second ionisation energy is of the element is measured
Na
Na+(g) —> Na2+(g) + e-
What is the observation when sodium is heated in oxygen
Bright yellow flame
White solid
