Atomic Structure & Periodic Table Flashcards
7 cards from real GCSE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Atomic Structure & Periodic Table flashcards as text
Mendeleev left gaps in his periodic table. Why was this considered a strength of his model?
Answer: The gaps successfully predicted properties of undiscovered elements
Mendeleev predicted elements like gallium and germanium, which were later discovered with properties matching his predictions.
Which of the following best explains why atoms are electrically neutral?
Answer: They contain equal numbers of protons and electrons
Protons carry +1 and electrons carry −1; equal numbers of each result in a net charge of zero.
Element Q has the electron arrangement 2,8,6. In which group and period is it found?
Answer: Group 6, Period 3
Period = number of occupied shells (3), Group = outer electrons (6), so Group 6, Period 3 — sulfur.
As you move down Group 1, the melting points of the alkali metals:
Answer: Decrease
Melting points decrease down Group 1 as atomic radius increases and metallic bonding becomes weaker.
A fluorine atom has 9 protons. A fluoride ion (F⁻) has:
Answer: 10 electrons
Fluorine gains 1 electron to form F⁻, so it has 9 protons and 10 electrons.
In the alpha particle scattering experiment, what did the mostly undeflected particles suggest about the atom?
Answer: The atom is mostly empty space
The vast majority passing straight through indicated that the atom is mostly empty space with mass concentrated in a tiny nucleus.
Which of the following pairs are isotopes of the same element?
Answer: ¹H and ²H
¹H (protium) and ²H (deuterium) are both hydrogen with 1 proton but different numbers of neutrons.