Answer:
C
Explanation:
Br + Br-> Br2 (covalent bond)
bond formation releases energy, as the Br's are in a lower energy state like Br2
Answer:
Ca(OH)₂ + H₂SO₄ → CaSO₄ + H₂O
Explanation:
Chemical equation:
Ca(OH)₂ + H₂SO₄ → CaSO₄ + H₂O
Balanced chemical equation:
Ca(OH)₂ + H₂SO₄ → CaSO₄ + 2H₂O
The given reaction is double displacement reaction in which anion and cation of both reactant exchanged with each other. Calcium hydroxide react with sulfuric acid and form calcium sulfate and water.
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AD +CB
Answer:
3 e⁻ transfer has occurred.
Explanation
This is a redox reaction.
- Oxidation (loss of electrons or increase in the oxidation state of entity)
- Reduction (gain of electrons or decrease in the oxidation state of the entity)
- An element undergoes oxidation or reduction in order to achieve a stable configuration. It can be an octet or duplet configuration. An octet configuration is that of outer shell configuration of noble gas.
- [Ne]= (1s²) (2s² 2p⁶)
A combination of both the reactions( Half-reactions) leads to a redox reaction.
Let us look at initial configurations of Al and Cl
[Al]= 1s² 2s² 2p⁶ 3s² 3p¹
[Cl]= 1s² 2s² 2p⁶ 3s² 3p⁵
Hence, Al can lose 3 electrons to achieve octet config.
and, Cl can gain 1e to achieve nearest noble gas config. [Ar]
This reaction can be rewritten, by clearly mentioning the oxidation states of all the entities involved.
Al⁰ + Cl⁰ → (Al⁺³)(Cl⁻)₃
Here, Aluminum is undergoing an oxidation(i.e loss of electrons) from: 0→(+3)
Chlorine undergoes a reduction half reaction (i.e gain of electrons) from: 0→(-1). There are 3 such chlorine atoms, hence 3 e⁻ transfer has occurred.
Weathering<span> breaks down and loosens the surface minerals of rock so they can be transported away by agents of erosion such as water, wind and ice. There are </span>two types<span> of </span>weathering<span>: </span>mechanical<span> and </span>chemical<span>. </span>Mechanical weathering<span> is the disintegration of rock into smaller and smaller fragments.</span>
Answer:
John Dalton
Explanation:
John Dalton in 1808 suggested that all matter consists of tiny particles called atoms and that the atoms of a specific element are identical.
He postulated the Dalton's atomic theory which has the following important parts;
- All matters consists of indivisible particles called atoms
- Atoms of the same element are similar and are different from atoms of other elements.
- Atoms can neither be created nor destroyed.
- Atoms combine in simple whole ratios to form compounds.
