What is the correct equation for the solubility product when calcium phosphate is dissolved in water

Which statement about the greenhouse effect is NOT true?

Archy [21]

Greenhouse gases were not historically present in the atmosphere.

7 0

3 years ago

The raw water supply for a community contains 18 mg/L total particulate matter. It is to be treated by addition of 60 mg alum (A

s344n2d4d5 [400]

Solution :

Given :

The steady state flow = 8000 $m^3 /d$

$= 80 \times 10^5 \ I/d$

The concentration of the particulate matter = 18 mg/L

Therefore, the total quantity of a particulate matter in fluid $= 80 \times 10^5 \ I/d \times 18 \ mg/L$

$= 144 \times 10^6 \ mg/g$

$= 144 \ kg/d$

If 60 mg of alum $[Al_2(SO_4)_3.14 H_2O]$ required for one litre of the water treatment.

So Alum required for $80 \times 10^5 \ I/d$

$= 80 \times 15^5 \ I/d \times 60 \ mg \ alum /L$

$= 480 \times 10^6 \ mg/d$

or 480 kg/d

Therefore the alum required is 480 kg/d

1 mg of the alum gives 0.234 mg alum precipitation, so 60 mg of alum will give $= 60 \times 0.234 \text{ of alum ppt. per litre}$

$= 14.04$ mg of alum ppt. per litre

480 kg of alum will give = 480 x 0.234 kg/d

= 112.32 kg/d ppt of alum

Daily total solid load is $= 144 \ kg/d + 112.32 \ kg/d$

= 256.32 kg/d

So, the total concentration of the suspended solid after alum addition $= 18 \ mg/L + 60 \times 0.234$

= 32.04 mg/L

Therefore total alum requirement = 480 kg/d

b). Initial pH = 7.4

The dissociation reaction of aluminium hydroxide as follows :

$Al(OH)_3 \rightleftharpoons Al^{3+} + 3OH^{-}$

After addition, the aluminium hydroxide pH of water will increase due to increase in $OH^-$ ions.

Therefore, the pH of water will be acceptable range after the addition of aluminium hydroxide.

c). The reaction of $CO_2$ and water as follows :

$CO_2 (g) + H_2O (l) \rightarrow H_2CO_3$

For the atmospheric pressure :

$p_{CO_2} = 3.5 \times 10^{-4} \ atm$

And the pH is reduced into the range of 5.9 to 6.4

6 0

3 years ago

How did Rutherford’s atomic model fix the shortcomings of Thomson’s atomic model?

dedylja [7]

Plum Pudding Model(Thomson's atomic model)

Thomson's atomic model states that an atom has a positive sphere charge with electrons embedded inside it. He compared the atom with a plum pudding,as the electrons according to him seemed like the dry fruits embedded in the spherical pudding.

Rutherford's Model

However Rutherford bombarded high energy streams of α-particles on a thin gold foil of 100 nm thickness. The deflection produced by the trajectory of these high energy α-particles after interaction with the thin sheet of gold was studied by placing a screen made up of zinc sulfide around the gold foil.
The major observations made by Rutherford were that a very huge fraction of α-particles passed through the gold sheet without getting deflected. Thus he concluded that the major part of an atom must be empty.
Very few α-particles got deflected minutely or at very small angles by the gold sheet when they were bombarded against it. Also very few particles got deflected at large angles. This made him conclude that the positive charge is concentrated in a very small region and is not distributed uniformly.

From the above observations he gave the following postulates:

An atom is made up of positively charged particles. The mass of an atom was concentrated in small region which is named as the nucleus of an atom.
The nucleus is surrounded by electrons which are negatively charged particles which revolve around the nucleus in a fixed circular path called as “orbits.”
An atom is electrically neutral because electrons are negatively charged and the nucleus is positively charged. The electrons are held by the nucleus due to a strong electrostatic force.
Compared to the total size of an atom the size of the nucleus is very small.

7 0

3 years ago

Which would MOST LIKELY produce more precipitation?

Sav [38]

Increased Evaporation/B is correct :p

6 0

3 years ago

All cartilage ossifies. True or false will mark brainliest!

chubhunter [2.5K]

I’m pretty sure true, just not your skull at birth hehe. hope this helps :)

6 0

3 years ago