Answer:
False
Explanation:
Laboratory synthesis of aspirin is done by the acetylation of salicylic acid with the help of acetic anhydride .
As , the acid anhydride is very sensitive to moisture , as it can hydrolyze into two molecules of acids,
Hence , the reaction involving acid anhydride are conducted in anhydrous solvents .
Hence ,
if water is present in the glassware then , some of the acetic anhydride is wasted , Which in turns reduces the yield than that expected .
Answer:
a) alkali metals
Explanation:
The element described above definitely belonged to the alkali metals, the first group on the periodic table. They show the properties indicated in the text.
- They are metals because only metals are lustrous and malleable. This eliminates the possibility of them being halogens and noble gases.
- Only group 1 metals reacts vigorously with water to form alkali.
- Alkali are aqueous solutions that are basic in nature.
- The reactivity of group 1 metals is due to their one extra electrons in the outer most shell.
- These electrons are easily and readily lost in order for such atoms to gain stability and replicate the nearest noble gases.
- The most reactive metal belongs to this group elements.
- This is why it is nearly impossible to find them occurring alone in free state.
- Some of the elements in this group are Li, Na, K, Rb, Cs and Fr.
- Transition metals have variable oxidation states and some can be found alone in nature.
If you were allowed to taste it sugar will be more sweeter whereas salt wouldnt. But if you were to touch it then sugar is more tinnier than salt.
Answer:
3. Sice increases, Ssw decreases, Ssys increases
Explanation:
Entropy basically refers to the degree of disorderliness of a system.
Ice Cube --> As the ice cube melts, it undergoes a change in state of matter from solid to liquid hence it's entropy increases as the degree of movement of its molecules is more disordered in the liquid state.
This means the likely options are; 1, 3 and 4.
Sidewalk --> The entropy here decreases as the ice melts on the side walk. This is because there is a reduction in temperature. Entropy is directly proportional to temperature. Decrease in temperature leads to decrease in entropy.
This means the likely option is 1 and 3
The net entropy change of the system is however positive.
