Answer:
The relationship is expressed as follows: ![K_{a} = \frac{[H+][A-]}{[HA]}](https://tex.z-dn.net/?f=K_%7Ba%7D%20%3D%20%5Cfrac%7B%5BH%2B%5D%5BA-%5D%7D%7B%5BHA%5D%7D)
Explanation:
Most acidic substances are weak acids and are therefore only partially ionized in acqeous solution. We cab use the equilibrium constant for the ionization of acid to express the extent to which the weak acid ionizes. If we represent a general weak acid as HA, we can write the equation for its ionization reaction like this:
To calculate the pH of a weak acid, we use the equilibrium concentration of the reacted species and product.
Take for example:
HA → H + A⁻
where A id the conjugate base.
Knowing that x amount of acid reacts, we can solve like this:
HA → H + A⁻
H+ = antilog (pH)
thus, the pH of the acid is equals to H+ (initial) - H+ (equilibrium) ≈ H+ (initial)
Answer : As the temperature of a medium increases, the speed of the sound wave increases because the particles bump into each other more often.
Explanation :
The dependency of the speed of the sound wave and the temperature of the medium is :
Where
= ratio of specific heat
R is gas constant
T is the temperature
The speed of the wave is directly proportional to the temperature. As the temperature of a medium increase, the speed of the sound increase. The particles start vibrating faster. Hence, they bump into each other.
Hence, the correct option is (A).
Answer:
13. 2g
14. 5000mL
15. 104,000m
16. 160mm
17. 5600000mg
18. 10hs
19. 0.250km
20. 1daL
Explanation:
13. 1000milligram (mg) = 1gram (g)
Hence, 2000mg = 2000/1000
= 2g
14. 1 litre (L) = 1000millilitre (mL)
Hence, 5L = 5 × 1000
= 5000mL.
15. 1kilometre (km) = 1000metre (m)
Hence, 104km = 104 × 1000
= 104,000m
16. 1 centimetre (cm) = 10millimeters (mm)
Hence, 16cm = 16 × 10
= 160mm
17. 1kilogram (kg) = 1000000 milligram (mg)
Hence, 5.6kg = 5.6 × 1000000
= 5600000mg
18. 1 second (s) = 0.01 hectosecond (hs)
Hence, 1000s = 1000 × 0.01
= 10hs
19. 1000metre (m) = 1kilometre (km)
Hence, 250m = 250/1000
= 0.250km
20. 1 centiliter (cl) = 0.001 Decaliter (daL)
Hence, 1000cl = 1000 × 0.001
= 1daL
Answer: increases by
As a chlorine atom becomes a negative ion, the atom "increases by" an electron
Explanation:
Chlorine atom has an atomic number of 17, and an electronic configuration of 1s2, 2s2 2p6, 3s2 3p5 showing 7 valence electrons in its outermost shell.
Hence, it receives a single electron to achieve a stable octet structure with electronic configuration of
1s2, 2s2 2p6, 3s2 3p6. Therefore, Cl- is a univalent negative ion with 8 valence electrons in its outermost shell. The increase is shown below
Cl + e- --> Cl-
Thus, as a chlorine atom becomes a negative ion, the atom "increases by" an electron
An atom always has the same number of protons and electrons, so it has 14 electrons.
Remembe! Dont get confused between at atom and an ion. Atoms have same number of protons and electrons but in an ion it differs,
