Zadanie 2d
Wzorowane na: Chemistry HL Paper 1B, May 2026, TZ3, pytanie 2(d). Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Informacja do zadań 2a-2d.
A group of students analysed freshly squeezed pink grapefruit juice. They determined the content of the red pigment lycopene, a carotenoid, by colorimetry, and the content of ascorbic acid, C6H8O6, by titration.
Polecenie
The students wished to compare their result for ascorbic acid with the value given for pink grapefruit juice in a food-composition database. Suggest two aspects of the data or of the samples that the students must check before judging whether their value agrees with the database value.
Sprawdź rozwiązanieUkryj rozwiązanieKlucz CKE i punktacja
Odpowiedź z klucza
Any two of:
the units in which the values are expressed ✔
the reliability / source of the database ✔
the analytical method used «to obtain the database value» ✔
the uncertainty / accuracy of the values ✔
the variety of grapefruit ✔
the ripeness of the fruit / the growing conditions ✔
whether the juice is fresh, stored or processed ✔
Schemat punktowania
[2 max]: one mark for each factor; apply the list principle. 'Human error' and other general statements about the quality of the students' work do not score.