Answer: The balance of the reaction shifts toward the endothermic reaction.
Explanation:
An ENDOTHERMIC REACTION requires input of HEAT ENERGY to drive it FORWARD from reactants, unto completion of products.
So, on increasing the temperature (available heat) the REVERSIBLE REACTION favors the shifts towards the endothermic reaction
US uses the <span>Fahrenheit temperature scale.</span>
Answer:
Other substances that give a positive test with AgNO3 are other chlorides present, iodides and bromide. However iodides and bromides have different colours hence they will not give a false positive test for KCl. Other chlorides present may lead to a false positive test for KCl.
Explanation:
In the qualitative determination of halogen ions, silver nitrate solution is used. Various halide ions give various colours of precipitate with silver nitrate. Chlorides yield a white precipitate, bromides yield a cream precipitate while iodides yield a yellow precipitate. All these ions or some of them may be present in the system.
However, if other chlorides are present, they will also yield a white precipitate just as KCl leading to a false positive test for KCl. Since other halogen ions yield precipitates of different colours, they don't lead to a false test for KCl. We can exclude other halides from the tendency to lead us to a false positive test for KCl but not other chlorides.
Heat energy is absorbed by the substance.
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.
