Answer:
CuCl2 + 2NaNO3 - > Cu(NO3)2 + 2NaCl
pH can be defined as negative logarithm of hydronium ion concentration .
pH can be mathematical represented as :
pH =-log [H+]
[H+]=2.3*10^-9
pH= -log[2.3*10^-9]
=8.64
Answer:
a. Ag+ and Ca2+
The pair of cations related to the question are as below:
a. Ag+ and Ca2+
b. Hg2^2+ and Ag^+
c. Ba^2+ and Na^+
d. Ca^2+ and Ba^2+
e. Pb^2+ and Ag^+
Explanation:
a. Ag+ and Ca2+ correct
Ag+ will precipitate with dilute hydrobromic acid (HBr) but Ca+2 will not
Ag+ + Br- -----------------> AgBr (s)
Ca+2 + 2Br- ---------------> CaBr2 (aq)
B) Hg2^2+ and Ag^+ Incorrect
Both Hg2^2+ and Ag^+ will precipitate. One has to precipitate while the other does not, so this is incorrect.
C) Ba2 and Na+ both won't precipitate. Incorrect
One has to precipitate while the other does not, so this is incorrect.
D) Ca2+ and Ba 2+both won't precipitate. Incorrect
One has to precipitate while the other does not, so this is incorrect.
E ) Both Pb2 and Ag+ will precipitate. Incorrect
One has to precipitate while the other does not, so this is incorrect.
One of the common indicators that a chemical reaction has occurred is if the react ants reacting produce a precipitate that is insoluble within the solution and forms.
Answer:
1. electrical conductor
2. orbit
3. potential energy
4. magnetic field
5. net force
6. B; repulsion
7. A; copper
8. B; there is no gravitational attraction between you and the cup, but Earth's gravity is stronger, so Earth's gravity pulls the cup down
9. A; the net force is acting in an upward direction
10. A; position 1
11. A; the gravitational force between two objects depends on their masses
12. C; the chemical potential energy of the spring is greatest at position 4
13. C; hand-held compass
14. C; a person skiing down a hill
15. A; the ions will repel each other
16. A; position A
17. three properties of magnets are attraction because they attract certain materials, repulsion because magnetic poles repel, and directive because a magnet that is freely suspended will always point in a north-south direction.
18. to increase the strength of an electromagnet you can either increase the strength current or increase the number of windings.
i hope this helps :)