Chemistry SL Paper 1A, specimen 2025

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 1

Which technique is used to obtain pure water from a solution of sodium chloride in water? A. evaporation B. distillation C. filtration D. paper chromatography

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 2

At 25 °C the density of heavy water, $\ce{^{2}H2O(l)}$, is 1.11 g cm⁻³, while the density of ordinary water, $\ce{^{1}H2O(l)}$, is 1.00 g cm⁻³. Which statement explains this difference? A. Each $\ce{^{2}H}$ nucleus contains one…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 3

Which electron transition in a hydrogen atom emits radiation with the longest wavelength? A. n = 2 to n = 1 B. n = 3 to n = 2 C. n = 4 to n = 3 D. n = 1 to n = 4

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

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

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Zadanie 5

A rigid cylinder of fixed volume contains N molecules of an ideal gas at 200 K and a pressure of 80 kPa. Half of the molecules are removed and the temperature of the remaining gas is raised to 500 K. What is the new pressure of the gas, in kPa? A. 16 B. 40…

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Zadanie 6

What is the formula of the compound formed between aluminium ions and sulfate ions? A. AlSO₄ B. Al₂(SO₄)₃ C. Al(SO₄)₃ D. Al₃(SO₄)₂

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 7

Which species contains a coordination bond? A. NH₃ B. H₃O⁺ C. CH₄ D. BF₃

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 8

Which properties of copper depend on the movement of its delocalized electrons? I. electrical conductivity of the molten metal II. thermal conductivity III. high density A. I and II only B. I and III only C. II and III only D. I, II and III

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Zadanie 9

The table shows the average electronegativity and the electronegativity difference for four substances, each made from two elements. Which substance is an alloy? A. P B. Q C. R D. S

• Tabela do uzupełnienia

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 10

Which structure shows the repeating unit of the addition polymer formed from pent-1-ene? A. [CH₂−CH₂−CH(CH₂CH₃)]_n B. [CH(CH₃)−CH(CH₂CH₃)]_n C. [CH₂−CH(CH₂CH₂CH₃)]_n D. [CH₂−C(CH₃)(CH₂CH₃)]_n

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 11

What is the explanation for the ductility of copper, which allows it to be drawn into wires? A. The attraction between the cations and the delocalized electrons is weak. B. The cations are held in the lattice by strong bonds that act in fixed directions. C.…

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Zadanie 12

Which functional groups are present in this molecule? A. halogeno, carboxyl, hydroxyl B. halogeno, carbonyl, hydroxyl C. halogeno, carbonyl, alkoxy D. halogeno, ester, hydroxyl

• Materiał graficzny

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 13

Element 117, tennessine, was first synthesized in 2010. In which block of the periodic table is it placed? A. s B. p C. d D. f

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Zadanie 14

Which is a correct alternative representation of the molecule shown? A. C₅H₁₁Br B. 3-bromo-2-methylbut-1-ene C. CH₂=CHC(CH₃)₂Br D. CH₃CH=C(CH₃)CH₂Br

• Materiał graficzny

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 15

The periodic table is divided into the s, p, d and f blocks. Which characteristic of an element determines the block in which it is placed? A. the number of protons in its nucleus B. the sublevel occupied by its highest-energy electrons C. the number of main…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 16

The enthalpy change of a reaction is ΔH = +58 kJ mol⁻¹. Which statement about this reaction is correct? A. The reaction is endothermic and the products are less stable than the reactants. B. The reaction is endothermic and the products…

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Zadanie 17

For which reactions can the enthalpy change be calculated using only average bond enthalpy data? I. N₂(g) + O₂(g) → 2 NO(g) II. C₂H₄(g) + H₂(g) → C₂H₆(g) III. 2 H₂O₂(l) → 2 H₂O(l) + O₂(g) A. I and II only B. I and III only C. II and III…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 18

Which energy source is renewable? A. natural gas B. biodiesel made from vegetable oil C. petrol (gasoline) refined from crude oil D. uranium

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 19

Ammonia is oxidized according to the equation below. 4 NH₃(g) + 5 O₂(g) → 4 NO(g) + 6 H₂O(g) What is the amount, in mol, of H₂O produced when 8.00 mol of NH₃ reacts with 5.00 mol of O₂, if the yield is 80 %? A. 4.80 B. 6.00 C. 9.60 D.…

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Zadanie 20

When 10.0 cm³ of a gaseous hydrocarbon, C_xH_y, is burned completely, 70.0 cm³ of gaseous products is formed. This volume falls to 30.0 cm³ when the water vapour condenses. All volumes are measured at the same…

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Zadanie 21

Propane hydrate, C₃H₈ ⋅ 17 H₂O (M_r = 350), is a crystalline solid that can form in natural gas pipelines at low temperature. What mass of carbon dioxide is produced by the complete combustion of 17.5 g of propane hydrate? A. 2.20 g B. 6.60 g C. 17.5 g…

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Zadanie 22

The diagram shows the energy profile of a reaction. P, Q and R are energies measured from the baseline of the potential energy axis. Which combination gives the activation energy of the forward reaction and the activation energy of the reverse reaction? A.…

• Materiał graficzny

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 23

The rate of the reaction between hydrogen and iodine vapour increases markedly when the temperature is raised from 500 K to 550 K. What is the main reason for this increase? A. The activation energy of the reaction is lowered. B. Molecules collide more…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 24

What is the equilibrium constant expression for the following reaction? CH₄(g) + H₂O(g) ⇌ CO(g) + 3 H₂(g) A. $\dfrac{[\ce{CH4}][\ce{H2O}]}{[\ce{CO}][\ce{H2}]^3}$ B. $\dfrac{3[\ce{CO}][\ce{H2}]}{[\ce{CH4}][\ce{H2O}]}$ C.…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 25

Which reactions involve the transfer of a proton? I. H₂SO₄(aq) + Zn(OH)₂(s) → ZnSO₄(aq) + 2 H₂O(l) II. H₂SO₄(aq) + ZnCO₃(s) → ZnSO₄(aq) + H₂O(l) + CO₂(g) III. H₂SO₄(aq) + Zn(s) → ZnSO₄(aq) + H₂(g) A. I and II only B. I and III only C. II…

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Zadanie 26

Calcium hydride is used as a portable source of hydrogen for fuel cells. It reacts with water as shown. CaH₂(s) + 2 H₂O(l) → Ca(OH)₂(aq) + 2 H₂(g) Which statement is correct? A. Calcium is reduced from +2 to 0. B. Hydrogen in CaH₂ is oxidized from…

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Zadanie 27

In a redox titration, dichromate(VI) ions are reduced to chromium(III) ions and iron(II) ions are oxidized to iron(III) ions. Cr₂O₇²⁻(aq) reduced to Cr³⁺(aq) Fe²⁺(aq) oxidized to Fe³⁺(aq) What volume, in cm³, of…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamkniętełatwe (szac.)

Zadanie 28

What is the organic product of the reaction of 2-bromobutane with aqueous potassium hydroxide? A. but-1-ene B. butan-1-ol C. butan-2-ol D. 2-bromobutan-2-ol

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 29

Methane reacts with chlorine in the presence of ultraviolet light. Two observations about this reaction are listed. - Observation 1: in the initiation step, Cl−Cl bonds undergo homolytic fission but C−H bonds do not. - Observation 2: the…

Chemia IBPaper 1A, specimen 2025wzorowane1 pktzamknięteśrednie (szac.)

Zadanie 30

Which species can act as an electrophile? A. CN⁻ B. NH₃ C. Br₂ D. Br⁻