Zapisujemy na Twoim urządzeniu to, bez czego serwis nie działa, np. zalogowanie. Plików analitycznych użyjemy tylko za Twoją zgodą. Szczegóły w polityce prywatności.
Baza zadań
Wybierz umiejętność, rok lub poziom trudności. Każde zadanie ma klucz i schemat punktowania.
Pokazujemy tylko poziomy, dla których mamy zadania.
Znaleziono 1061 zadań
(i) Determine the limiting reactant when 2.00 g of this powder reacts. (ii) Determine the volume, in dm3, of carbon dioxide released in the reaction in (i) at SATP. Use sections 1, 2 and 4 of the data booklet. (iii) A student collects 0.190…
The structure of a tartaric acid molecule is shown. (i) State how many hydrogen atoms in a tartaric acid molecule are acidic. (ii) Deduce the structural formula of the conjugate base of tartaric acid. (iii) Predict, giving a reason, whether tartaric acid is a…
A solution has a hydrogen ion concentration [H+] = 0.0063 mol dm−3. Calculate its pH.
The data for 0.6 g of catalyst seem anomalous. Suggest a possible cause.
The student hypothesized, from theory, that doubling the mass of CuO would double the rate of the catalysed reaction. (i) Suggest why it is important to state a hypothesis before an experiment is carried out. (ii) Explain how collision theory could…
The results in Figure 1 were processed to give Figure 2, which shows how the initial rate of reaction varies with the mass of catalyst. (i) Outline how the y-axis values in Figure 2 were obtained from the results in Figure 1. (ii) Suggest, giving a reason,…
Which compound has the highest percentage of carbon by mass? A. CH3CH2OH B. CH3CHO C. C3H8 D. C2H6
Outline why compound A cannot be a hydrocarbon.
Determine the empirical formula of A.
At 150.0 °C and a pressure of 1.00 × 105 Pa, the vapour of A has a density of 2.45 × 103 g m−3. Determine the molar mass of A and hence its molecular formula. Use sections 1 and 2 of the data booklet.