Answer:
∆H or Enthalpy of the reaction
Explanation:
If ∆H is +ve
- Reaction is exothermic
- Example:-Combustion, mixing sodium/potassium in water
If ∆H is -ve
- Reaction is endothermic
- Ex:-Melting of ice
Answer: A curve showing the relationship between temperature and time for a given amount of liquid heated at constant rate is a heating curve.
This is the option a. heating.
The increase of temperatue as result of heating may be ploted to show the changes. This increase of temperature related with the heat depends of the heat capacity of the substance. For a fixed amount of heat, substances with high heat capacity exhibit a lower increase in temperature than substances with low heat capacity.
Answer:
Fe(OH)2
Explanation:
Iron hydroxides are chemical compounds that appear as precipitates after alkalizing solutions containing iron salts, both in their valence or degree of oxidation (III) and (II).
Hydroxide, in both cases, is a gelatinous colloid of difficult filtration that can be considered a hydrated oxide, iron (II) hydroxide is whitish in color and requires more alkalinization, above 7.
Answer:
(b) Trigonal planar
Explanation:
The molecular geometry is the one that stabilizes better the bonds and the free electron pairs. If the molecule is nonpolar (overall dipole moment zero), so, there's no free electron pairs at the central atom. So, the molecule has the central atom A surrounded by three atoms of B, which is the trigonal planar geometry.
