Zadanie 28
Wzorowane na: Chemistry SL Paper 1, May 2024, TZ1, pytanie 28. Treść, dane i kontekst są zmienione; sprawdzane umiejętności, format i punktacja jak w oryginale.
Darmowe konto pozwoli wrócić do niego później.
Polecenie
Four 25.0 cm3 samples of water were measured using a graduated cylinder and each was weighed. The masses were 24.4 g, 25.6 g, 24.8 g and 25.2 g. The density of water under the conditions of the experiment is 1.00 g cm−3.
What is the best description of the measurements?
A. accurate and precise
B. accurate but not precise
C. precise but not accurate
D. neither accurate nor precise
Sprawdź rozwiązanieUkryj rozwiązanieKlucz i punktacja
Odpowiedź z klucza
B ✔
«25.0 cm3 of water has a mass of 25.0 g; the mean of the four masses is (24.4 + 25.6 + 24.8 + 25.2)/4 = 25.0 g, so the measurements are accurate (the mean agrees with the true value); the individual values scatter over a range of 1.2 g, so they are not precise»
Schemat punktowania
One mark for the correct option.