Answer:
2 only
Explanation:
Electrons are filled in atoms according to the Aufbau principle. Electrons are filled into lower energy orbital before the filling of higher energy orbitals and this sequence must be followed in filling electron orbitals.
The order of arrangement of energy levels may be shown as follows; 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p. This implies that 4f>6s, hence 6s is filled before 4f.
Also, the 6p level > 5d level hence this is the correct option. You must fill the 5d level before you feel the 6p level.
Atom is the
most basic unit of matter. They are the general term used to describe pieces of
matter. But a different kind of atom makes up an element. A combination of atom of different elements
creates a molecule. For example, you have water; it has a chemical formula of
H2O. If you separate H from O, you have two atoms. Two atoms for hydrogen and
one atom for oxygen. However, they are of different elements. And when you
combine them to form H2O, you create a molecule.
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Answer:
It is not a gas because its particles do not have large spaces between them.
Explanation:
Solids and liquids have a lot of particles with few spaces between them. Also, gas particles move rapidly in each direction.
1. This can be due to the dissolving of the solid in liquid and form a solution.
Dissolving is a physical property because dissolving doesn't form new substances and the chemical composition of the solid is not changed.
The color building up over the time can be due to the rate of dissolving of the solid and amount of particles have been dissolved.
Example:
- Dissolving of CuSO₄ solid in water.
- This develops a blue color.
2. This can be due to the chemical reaction between the solid and liquid.
Chemical reaction is a chemical property because from reacting substances new substances can be formed which the chemical formula is different from initial substances.
The color building up over the time can be due to the rate of the reaction and the amount of reactants.
Example:
- The reaction between calcium metal with water.
- The color of Ca(OH)₂ is white color.
- Reaction is
Ca(s) + 2H₂O(l) → Ca(OH)₂(aq) + H₂(g)
The answer is cadmium its got 48 electrons which is y its number 48 on the period table
