D. All of the above are indicators of chemical change
Answer:did you get the answer
Explanation:
1. <span>Count Sergei Lvovich Levitsky invented the Bellows camera. The correct option among all the options that are given in the question is the last option or option "D".
2. The substance with which the first photograph was made from, was Bitumen. The correct option among all the options given in the question is the first option or option "A".
3. Kodak DCS 100 was the first commercially available digital camera. The correct option among all the options that are given in the question is the first option or option "A".</span>
<span>H2CO3 <---> H+ + HCO3-
NaHCO3 <---> Na+ + HCO3-
When acid is added in the buffer, the excess H+ of that acid reacts with HCO3- to form H2CO3, and due to this NaHCO3 dissociates into HCO3- to attain the equilibrium. and hence there is no net effect of H+ due to pH remain almost constant.
when a base is added to the buffer, the OH- ion of base react eith H+ ion present in buffer, then to attain equilibrium of H+ ion, the H2CO3 dissociates to produce H+ ion, but now there is the excess of HCO3- due to which Na+ ion react with them to attain equilibrium of HCO3-. hence there is again no net change in H+ ion due to which pH remain constant.....</span>
Explanation:
the inner core is solid. the outer core is liquid
