3) Answer is: because elements have different emmision spectrum.
Emission spectrum of a chemical element is the spectrum of frequencies emitted due to an atom making a transition from a high energy state to a lower energy state. Each element's emission spectrum is unique.
4) Answer is: lithium chloride and sodium chloride do not have similar colors.
Lithium ion has red and sodium ion has yellow emission spectrum.
5) Answer is: because metals have valence electrons in different energy shells.
Each transition has a specific energy difference.
6) Answer is: salts of alkaline and earth alkaline metals.
For example barium chloride gives green light.
Answer:
Sodium hydroxide solution.
Explanation:
because it is a strong base. Since carbonic acid is a weak acid, a solution formed resists change in pH on addition hence buffer formed.
The correct answer is a. This is because the pH of a solution is defined as -log10(concentration of H+ ions). An inverse logarithmic scale such as this means that a solution with a lower concentration of H+ ions will have a higher pH than one with a higher concentration. Therefore we know that the pH of the second sample will be higher than the first.
Since the logarithmic scale has the base 10, a change by 1 on the scale is a consequence of multiplication/division of the H+ concentration by a factor of 10. As the scale is inverse, this means that a decrease of concentration by factor 1000 is equivalent to increasing the pH by (1000/10) = 3.
Saturated hydrocarbons consists of C-C single bond whereas Unsaturated hydrocarbons consists C-C double/triple bond.