What is the name of an element that have a atomic number of 82 and the atomic number of 207

Plz answerrrr I dunnoooo

aleksley [76]

Midnight is your answer.

plz mark as brainliest. i really need it ;-;.

Just ask if you need more help

3 0

3 years ago

Read 2 more answers

What volume does .0685 mol of gas occupy at STP? 1mole =22.4

GuDViN [60]

V = nRT/P
V = 0.685 mol*(.0821 L*atm/K*mol)*273 K/1 atm

4 0

3 years ago

Read 2 more answers

4. Know the location of metals, non-metals and metalloids

erastovalidia [21]

Answer:

The metals are to the left of the line (except for hydrogen, which is a nonmetal), the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids.

Hope this helped

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

The fact that same molecules of matter have been around for years is supported by

Elza [17]

Answer:

The law of definite proportions

Explanation:

The law of definite proportions states that atoms combine in a molecule in a specific molar ratio or specific stoichiometry. For example, it's proved that regardless of the quantity we take, two hydrogen atoms always combine with one oxygen atom to form a water molecule.

Similarly, ionic substances follow the same pattern. Since the net charge of ionic salts should be equal to 0 and each element has a definite number of valence electrons in its shell all the time, the ions combine in a way, so that cations balance the charge of anions.

Essentially, the law of definite proportions is applicable and will be applicable in the future, since we know that each element has a fixed number of valence electrons in its ground state.

6 0

3 years ago