Zadanie 5
Wzorowane na: Chemistry HL Paper 1, November 2023, TZ1, pytanie 5. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
The first three ionization energies of two elements, X and Y, are given in the table.
| Element | First / kJ mol⁻¹ | Second / kJ mol⁻¹ | Third / kJ mol⁻¹ |
|---|---|---|---|
| X | 578 | 1817 | 2745 |
| Y | 738 | 1451 | 7733 |
Which pair of elements are X and Y, in that order?
A. Aluminium and magnesium
B. Magnesium and aluminium
C. Sodium and magnesium
D. Sodium and aluminium
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
A ✔
«Y: the very large jump between the second and third ionization energies shows that the third electron comes from an inner energy level, so Y has two valence electrons (group 2, magnesium); X: no such jump after the third value (2745 is only slightly larger than 1817), so three electrons are removed from the outer energy level (group 13, aluminium)»
Schemat punktowania
One mark for the correct option.