Classify each of the following substances as either a strong or weak acid, strong or weak base, or a soluble or insoluble salt.
1. hclo4
2. pbcl2
3. koh
4. hno2
5. nabr
a. strong acid
b. weak acid
c. strong base
d. weak base
e. soluble salt
f. insoluble salt

KOH is a strong base, is a strong acid, is a weak acid, NaBr is a soluble salt and is an insoluble salt

Explanation:

According to solubility rule, all chlorides, bromides and iodides of metal ions are soluble except for and Hg^{+}[/tex].

Therefore NaBr is a soluble salt and is an insoluble salt.

There are seven strong acids : HCl, HBr, HI, , , and .

All group IA metal hydroxides e.g. NaOH, KOH etc. are strong base. Also, , and are strong bases.

So, KOH is a strong base, is a strong acid and is a weak acid.

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j