What is the chemical formula for ammonium sulfate?

How many moles are in 7.2x10^15 atoms of Pb?

fiasKO [112]

<h3>Answer:</h3>

1.2 × 10⁻⁸ mol Pb

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[Given] 7.2 × 10¹⁵ atoms Pb

<u>Step 2: Identify Conversions</u>

Avogadro's Number

<u>Step 3: Convert</u>

[DA] Set up: $\displaystyle 7.2 \cdot 10^{15} \ atoms \ Pb(\frac{1 \ mol \ Pb}{6.022 \cdot 10^{23} \ atoms \ Pb})$
[DA] Multiply/Divide [Cancel out units]: $\displaystyle 1.19562 \cdot 10^{-8} \ mol \ Pb$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 2 sig figs.</em>

1.19562 × 10⁻⁸ mol Pb ≈ 1.2 × 10⁻⁸ mol Pb

6 0

2 years ago

Find the total number of moles of ions produced when 0.347 mol of sodium carbonate dissolves.

Ahat [919]

Answer:

molarity= 0.238 mol L-

Explanation:

The idea here is that you need to use the fact that all the moles of sodium phosphate that you dissolve to make this solution will dissociate to produce sodium cations to calculate the concentration of the sodium cations.

Na 3 PO 4 (aq) → Na + (aq) + PO3−4 (aq)

Use the molar mass of sodium phosphate to calculate the number of moles of salt used to make this solution.

3.25g⋅1 mole N 3PO4 163.9g = 0.01983 moles Na3 PO 4

Now, notice that every

1 mole of sodium phosphate that you dissolve in water dissociates to produce

3bmoles of sodium cations in aqueous solution.

4 0

2 years ago

Which branch of the chemical industry usually requires advanced degrees? Marketing product development R & D corporate manag

fredd [130]

Answer: R & D is the correct option.

Explanation:

Research and development department of a chemical industry requires individuals holding advanced degrees because :

This will help the chemical industry to come up with new developments and advancements in preparation of the chemical products like :green methods to prepare certain chemicals which usually involves handling of toxic substances.
Formulation and development of the new chemical substitutes
Improvement of chemical product at microscopic level.

4 0

2 years ago

A car with a mass of 1,200 kilograms is moving around a circular curve at a uniform velocity of 20 meters per second. The centri

Helga [31]

The answer is 80 m.

Centripetal force (F) is a force that makes body move around a circular curve. The unit of force is N (N = kg * m/s²).
It can be represented as:
$F= \frac{m* v^{2} }{r}$
where:
m - mass
v - velocity
r - radius of the curve

We have:
m = 1,200 kg
V = 20 m/s
F = 6,000 N = 6,000 kg * m/s²

We need radius of the curve:
r = ?

So, if <span> $F= \frac{m* v^{2} }{r}$ , then:
</span> $r= \frac{3* v^{2} }{F}$
⇒ $r = \frac{1200 kg * (20m/s)^{2} }{6000 kg*m/s^{2} }$
⇒ $r= \frac{1200*400*kg*m^{2}*s^{2} }{6000kg*m/s^{2} }$
⇒ $r= \frac{480,000m}{6000}$
⇒ $r=80m$

6 0

3 years ago

When light energy excites electrons in photosystem II, where do the electrons to replace them come from?

Artyom0805 [142]

Oh we have just done this in biology recently... photolysis occurs where it splits apart water molecules to make electrons and hydrogen ions (the H+ is used to reduce NaDP later on) and also O₂ is made as a by product

basically this is the equation 2H₂O⇒4e⁻ + 4H⁺ where the electrons replace the lost ones in chlorophyll

hope this helped :)

3 0

3 years ago