Answer:
B. Element
Explanation:
Tungsten is an chemical element
We assume that we have Ka= 4.2x10^-13 (missing in the question)
and when we have this equation:
H2PO4 (-) → H+ + HPO4-
and form the Ka equation we can get [H+]:
Ka= [H+] [HPO4-] / [H2PO4] and we have Ka= 4.2x10^-13 & [H2PO4-] = 0.55m
by substitution:
4.2x10^-13 = (z)(z)/ 0.55
z^2 = 2.31x 10^-13
z= 4.81x10^-7
∴[H+] = 4.81x10^-7
when PH equation is:
PH= -㏒[H+]
= -㏒(4.81x10^-7) = 6.32
Answer:
Options B and C
Explanation:
Let's take a look at the options and get our answer by way of elimination. The basic definition of a neutral solution is given as;
A neutral solution is a substance which is neither acid nor basic . it has a PH of 7. it will have equal amount of H+ AND OH- ions in it.
a) a neutral solution does not contain any H3O+ or OH- This is wrong because take water as an example, it is neutral but contains both ions.
b) a neutral solution contains [H2O] = [H3O+]. This option is correct cause it is in line with the definition above.
c) an acidic solution has [H3O⁺] > [OH⁻]. Acidic solutions are any solution that has a higher concentration of hydrogen ions than water. This option is correct.
d) a basic solution does not contain any H3O⁺. This option is wrong. Basic solutions are any solution that has a higher concentration of hydroxide ions than water. This means they contain H3O⁺ but [OH⁻] is greater.
Answer:
No reaction
Explanation:
Single-displacement reaction is the chemical reaction in which one metal which has higher negative redox potential replaces the another from it's salt solution.
Thus, Cu cannot replaces zine from its salt as it is less reactive than zince.
However, zinc can replace copper from its salt as:

Answer:
it's an indicator that a chemical reaction occurred.