Paper 1 Exam Questions Flashcards
Describe a method to make pure, dry crystals of magnesium sulfate from a metal
oxide and a dilute acid.
[6 marks]
- use magnesium oxide and sulfuric acid
- add sulfuric acid to a beaker
- warm sulfuric acid
- add magnesium oxide
- stir
- continue adding until magnesium oxide is in excess
- filter
- using a filter paper and funnel
- to remove excess magnesium oxide
- heat solution in an evaporating basin
- to crystallisation point
- leave to crystallise
- pat dry with filter paper
Nickel is extracted from nickel oxide by reduction with carbon. box
Explain why carbon can be used to extract nickel from nickel oxide.
[2 marks]
-
carbon is more reactive (than
nickel) - (so) carbon will displace /
replace nickel (from nickel
oxide)
Chadwick’s experimental work on the atom led to a better understanding of isotopes. Explain how his work led to this understanding. [3 marks]
Chadwick provided the evidence to show the existence of neutrons (this was necessary because) isotopes have the same number of protons or (this was necessary because) isotopes are atoms of the same element but with different numbers of neutrons
The temperature change depends on the reactivity of the metal.
The student’s results are used to place copper, iron, magnesium and zinc in order of their reactivity.
Describe a method to find the position of an unknown metal in this reactivity series.
Your method should give valid results. [4 marks]
add the unknown metal to copper sulfate solution (1)
measure temperature change (1)
place the metals in order of temperature change (1)
any one from (1):
- same volume of solution
- same concentration of solution
- same mass / moles of metal
- same state of division of metal
Explain why graphite conducts electricity. Answer in terms of the structure and bonding in graphite
each carbon / atom forms 3 (covalent) bonds
one electron per carbon / atom is delocalised
(so) these electrons carry charge through the graphite or (so) these electrons move through the structure
Calculate the amount in moles of chlorine collected after 20 minutes.
Use Figure 8. The volume of one mole of any gas at room temperature and pressure is 24.0 dm3 Give your answer in standard form. [3 marks]
volume was 6.6 cm^3 from Fig 8
(volume=) 6.6 1000 (dm3 )
or 0.0066 (dm3 )
(moles=) 0.0066/24
= 2.75 × 10−4 (mol)
(bonds broken = 4(412) + 193 =)1841
(bonds formed = 3(412) + 366 + X =) 1602 + X
−51 = 1841 − (1602 + X)
(X =) 290 (kJ/mol)
Titanium chloride is a liquid at room temperature.
Explain why you would not expect titanium chloride to be a liquid at room temperature
metal chlorides are usually ionic
so) (metal chlorides) are solid at room temperature
(because) they have strong (electrostatic) forces between the ions
Titanium chloride is a liquid at room temperature.
Explain why you would not expect titanium chloride to be a liquid at room temperature
Dilute hydrochloric acid is a strong acid.
Explain why an acid can be described as both strong and dilute.
(strong because) completely ionised (in aqueous solution)
(dilute because) small amount of acid per unit volume
Sodium is in Group 1 of the modern periodic table.
Describe what you would see when sodium reacts with chlorine. [2 marks]
- flame
- (white) solid forms
- colour of gas / chlorine disappears / fades
5.6)
the products have 1272 (kJ) less energy than the reactants
(so) energy is released (to the surroundings)
A student is given three metals, X, Y and Z to identify.
The metals are magnesium, iron and copper.
Plan an investigation to identify the three metals by comparing their reactions with dilute hydrochloric acid.
Your plan should give valid results. [4 marks]
electrostatic force of attraction between shared pair of negatively charged electrons
and both positively charged nuclei
