Liquid - rain
Solid - snow
Gas - water vapour (when it evapourates from the lithosphere)
Answer:
1. The α particles were repelled by electrons.
Explanation:
The gold foil experiment was performed by Rutherford and his research group in 1911 (at the beginning of the 20th century). In this experiment, α particles were bombed to gold foils, and films were placed surround it to collect the particles.
It was observed that most of the particles passed through of the foil undeflected, and for that, Rutherford stated that the atom was a "huge empty". Some particles were deflected, because they're attracted to the electrons at the electrosphere, and a small number of particles were complete deflected to the origin because they chocked with the small positive nuclei.
Thus, the experiment suggested the nuclear model of the atom, called the planetary model, that was improved after by Bohr and other scientists in the quantum model.
A mole is a unit to describe an amount of something/specific substance. Typically standard for measuring a large quantity of small entities like atoms, molecules, or other particles.
Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶
Density of iron bar
= 7870 kg/m³ (3 s.f.)
7.
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
(3 s.f.)
A good feeling, but i'm not sure what it's called
