The scientist John Dalton lived over 200 years ago - Edexcel - GCSE Chemistry Combined Science - Question 5 - 2021 - Paper 1
Question 5
The scientist John Dalton lived over 200 years ago.
(a) John Dalton suggested an early model of atoms.
When Dalton first described atoms he said that
- all element... show full transcript
Worked Solution & Example Answer:The scientist John Dalton lived over 200 years ago - Edexcel - GCSE Chemistry Combined Science - Question 5 - 2021 - Paper 1
Step 1
Give two differences between Dalton's model of atoms and today's model of atoms.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Dalton's model suggested that atoms were indivisible, while today's model recognizes that atoms can be divided into subatomic particles (protons, neutrons, and electrons).
Dalton's model proposed that all atoms of the same element are identical, whereas modern atomic theory acknowledges the existence of isotopes, which are atoms of the same element that have different numbers of neutrons.
Step 2
Give the molecular formula and the empirical formula of ethene.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The molecular formula of ethene is C₂H₄.
The empirical formula, which represents the simplest whole-number ratio of the elements, is CH₂.
Step 3
Complete the balanced equation for this reaction, including the three missing state symbols.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The balanced equation is:
Cl₂ (g) + H₂O (l) = 2 HCl (aq) + HClO (aq).
Step 4
Give the formula of the ion in Figure 6 that causes the hydrogen chloride solution to be acidic.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The formula of the ion that causes the hydrogen chloride solution to be acidic is H⁺.
Step 5
Give the name of this type of reaction.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
This type of reaction is called a neutralisation reaction.
Step 6
Describe what you would see when some copper carbonate powder is added to a beaker of dilute sulfuric acid.
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
When copper carbonate powder is added to dilute sulfuric acid, a reaction occurs that produces carbon dioxide gas. You would see effervescence (bubbles) as the carbon dioxide is released. Additionally, the blue color of the copper carbonate may gradually disappear as it reacts to form copper sulfate.
