To find the maximum amount of copper (in grams) allowed in 100 g of water use the maximum amount ratio (1.3 mg / kg) and set a proportion with the unknown amount of copper (x) and the amount of water (100 g):

First, convert 100 g of water to kg: 100 g × 1 kg / 1000 g = 0.1 kg.

Now, set the proportion:

1.3 mg Cu / 1 Kg H₂O = x / 0.1 kg H₂O

Solve for x:

x = 0.1 kg H₂O × 1.3 mg Cu / 1 kg H₂O = 0.13 mg Cu

Convert mg to grams:

0.13 mg × 1 g / 1,000 mg = 0.00013 g

Answer: 0.00013 g of copper.

6 0

3 years ago

How many molecules are in 0.0740 mol NH3?

Mariana [72]

Number of molecules NH₃ = 4.45 x 10²²

<h3>Further explanation </h3>

A mole is a number of particles(atoms, molecules, ions) in a substance

This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles

Can be formulated :

N = n x No

N = number of particles

n = mol

No = 6.02.10²³ = Avogadro's number

mol of NH₃ = n = 0.074

So the number of molecules :

$\tt N=n\times No\\\\N=0.0740\times 6.02\times 10^{23}\\\\N=4.45\times 10^{22}$

3 0

3 years ago

Suppose that in an ionic compound, "m" represents a metal that could form more than one type of ion. in the formula mf2 , the ch

geniusboy [140]

F (Fluorine) is in column (group/family) VIIA, or the "halogens". When you see the halogens (Fluorine, Chlorine, Bromine, and Iodine) in combination with a metal, each halogen atom present will carry a -1 charge. We can see that the atom has no charge, so the metal must cancel out the negative charges brought by the two fluorine atoms.
(Charge on m) + 2*(charge on fluorine) = 0
(Charge on m) + 2*(-1) = 0
(Charge on m) - 2 = 0
Charge on m ion = +2

3 0

3 years ago