Zadanie 4
How many ions are present in 142 g of Na2SO4? M(Na2SO4) = 142 g mol−1 A. 1 B. 3 C. 6.02 × 1023 D. 1.81 × 1024
The mole and the Avogadro constant
Define the mole as the SI unit of amount of substance, use the Avogadro constant (6.02 × 10²³ mol⁻¹) to convert between moles and numbers of atoms, molecules, ions or electrons, and count particles inside a formula (oxygen atoms in 2 mol of H2SO4).
Tę umiejętność sprawdza 12 zadań wzorowanych na arkuszach IB z lat 2022–2026.
Zadania sprawdzające tę umiejętność: 12 Otwórz w wyszukiwarce z filtrami
Zadanie 4
What is the number of hydrogen atoms in 0.200 mol of propylamine, C3H7NH2? NA = 6.02 × 1023 mol−1 A. 1.20 × 1023 B. 1.08 × 1024 C. 8.43 × 1023 D. 1.08 × 1025
Zadanie 1
What is the number of hydrogen atoms in 0.0500 mol of hydrated magnesium sulfate, MgSO4 ⋅ 7 H2O? A. 3.01 × 1022 B. 4.21 × 1023 C. 2.11 × 1023 D. 4.21 × 1022
Zadanie 1b
4.81 g of sulfur was heated in a stream of chlorine gas until the reaction was complete. The mass of the chloride produced was 10.13 g. (i) Calculate how many atoms are present in this 4.81 g sample of sulfur. Use sections 2 and 7 of the data booklet. (ii)…
Zadanie 3
What is the total number of ions in 0.30 mol of iron(III) nitrate, Fe(NO3)3? A. 0.30 × 1 × 6.02 × 1023 B. 0.30 × 3 × 6.02 × 1023 C. 0.30 × 4 × 6.02 × 1023 D.…
Zadanie 4
A sealed flask contains 8.0 g of helium and 120 g of argon. What is the ratio of the number of atoms of argon to the number of atoms of helium in the flask? A. 0.067 B. 0.67 C. 1.5 D. 15
Zadanie 4
What is the number of hydrogen atoms in 0.400 mol of propane, C3H8? Avogadro's constant (L or NA) = 6.02 × 1023 mol−1 A. 2.41 × 1023 B. 7.22 × 1023 C. 1.44 × 1024 D.…
Zadanie 2
What is the mass of one molecule of white phosphorus, P4? Use NA = 6.02 × 1023 mol−1. A. 5.1 × 10−23 g B. 2.1 × 10−22 g C. 4.9 × 1021 g D. 7.5 × 1025 g
Zadanie 8b
Glucose, C6H12O6, is a monosaccharide that is oxidized in the body to carbon dioxide and water. The standard enthalpy change of combustion of glucose is −2803 kJ mol−1. Calculate the energy, in kJ, released by the complete combustion of…
Zadanie 4c
Iron has a number of natural isotopes. A sample of iron was enriched in to produce a mixture with the following composition: (i) Calculate the relative atomic mass of the enriched sample, giving your answer to two decimal places. (ii) Natural…
- Tabela do uzupełnienia
Zadanie 2
Which sample contains the fewest moles of HBr? NA = 6.02 × 1023 mol−1. Molar volume of an ideal gas at STP = 22.7 dm3 mol−1. A. 0.647 g of HBr(g) B. 50.0 cm3 of…
Zadanie 1
How many oxygen atoms are present in 0.0200 mol of aluminium sulfate, Al2(SO4)3? NA = 6.02 × 1023 mol−1 A. 1.20 × 1022 B. 4.82 × 1022 C. 1.44 × 1023 D. 1.44 × 1024