Identify the state of matter in between C&D.

The first method of determining the chemical composition of substances in space was to _____.

Art [367]

Answer:The first method to determine the chemical composition of a substance in space was using light. By determining red shift in the observed spectrum of light they could determine the elements they were observing

Explanation:

5 0

3 years ago

A 250.0-ml sample of ammonia, nh3 (g), exerts a pressure of 833 torr at 42.4 °c. what mass of ammonia is in the container

Lelu [443]

To solve this, let's assume ideal gas behavior.

PV=nRT
Let's solve for n. Convert units to SI units first.

Pressure = 833 torr(101325 Pa/760 torr) = 111,057.53 Pa
Volume = 250 mL(1 L/1000 mL)(1 m³/1000 L) = 2.5×10⁻⁴ m³
Temperature = 42.4 + 273 = 315.4 K

n = (8,314 J/mol·K)(315.4 K)/(111057.53 Pa)(2.5×10⁻⁴ m³)
n = 94.45 mol

The molar mass of ammonia is 17.031 g/mol.
Mass = 94.45*17.031 = 1,608.51 g ammonia

6 0

4 years ago

2. If you have 8.08 g of hydrogen, how many grams of ammonia will your produce?

Nikolay [14]

answer: Stoichiometry is a big word for a process that chemist’s use to calculate

amounts in reactions. It makes use of the coefficient ratio set up by balanced

reaction equations to make connections between the reactants and products

in reactions.

 Stoichiometry calculates the quantities of reactants and products in a

chemical reaction. The equation must be balanced!

 Questions that deal with amounts in reactions are examples of reaction

stoichiometry. We already have the tools necessary to solve this question.

We just need to learn a new way to apply skills such as writing chemical

formulas, calculating formula masses, and converting from mass to moles,

particles to moles, and volume of gases to moles.

 Mole to Mole Conversions- you must have the Mole Ratio.

Illustration:

Let’s use an analogy that we can understand to begin to understand the process.

The KEY to any mole conversion is the ratio of coefficients in the reaction

equation. Say I want to make a bacon double cheeseburger. Let’s get our recipe

together.

1 hamburger bun + 2 hamburger patties + 2 slices of cheese + 4 strips of bacon →

1 bacon double cheeseburger

Based on this recipe:

1) If I have five bacon double cheeseburgers:

a. How many hamburger buns did you use? → 5 hamburger bun

b. How many hamburger patties did you use? → 10 hamburger patties

c. How many slices of cheese did you use? → 10 slices of cheese

d. How many strips of bacon did you use? → 20 strips of bacon

2) How many bacon double cheeseburgers can you make if you start with:

a. 2 buns, 4 patties, 4 slices of cheese, 8 strips of bacon

2 bacon double cheese burgers

b. 1 dozen buns, 2 dozen patties, 2 dozen slices of cheese, 4 dozen strips of bacon

1 dozen bacon double cheese burgers

7 0

3 years ago

Be sure to answer all parts. one of the most important industrial sources of ethanol is the reaction of steam with ethene derive

lions [1.4K]

Answer: 2.17x10⁻³ atm

Explanation:

First, we must write the balanced chemical equation for the process:

C₂H₄(g) + H₂O(g) ⇌ C₂H₅OH(g)

The chemical reactions that occur in a closed container can reach a state of chemical equilibrium that is characterized because the concentrations of the reactants and products remain constant over time. The equilibrium constant of a chemical reaction is the value of its reaction quotient in chemical equilibrium.

The equilibrium constant (K) is expressed as the ratio between the molar concentrations (mol/L) of reactants and products. Its value in a chemical reaction depends on the temperature, so it must always be specified.

We will use the the equilibrium constant Kc of the reaction to calculate partial pressure of ethene. The constant Kc for the above reaction is,

Kc = $\frac{[C_{2} H_{5}OH]}{[H_{2}O][C_{2} H_{4}]}$

According to the law of ideal gases,

PV = nRT

where P, V, n and T are the pressure, volume, moles and temperature of the gas in question while R is the gas constant (0.082057 atm L / mol K) .

We can use the ideal gas law to determine the molar concentrations ([x] = n / V) from the gas pressures of ethanol and water, assuming that all gases involved behave as ideal gases. In this way,

PV = nRT → P = (n/V) RT → P = [x] RT → [x] = P / RT

So,

$[C_{2} H_{5}OH] = \frac{200 atm}{0.082057 \frac{atm L}{mol K} x 600 K } = 4.06 \frac{mol}{L}$

$[H_{2}O] = \frac{400 atm}{0.082057 \frac{atm L}{mol K} x 600 K } = 8.12 \frac{mol}{L}$

So, the molar concentration of ethene (C₂H₄) will be,

$[C_{2} H_{4}] = \frac{[C_{2} H_{5}OH]}{[H_{2}O] x Kc} = \frac{4.06 \frac{mol}{L} }{8.12 \frac{mol}{L}x9.00 x 10^{3} \frac{L}{mol} } = 5.56 x 10^{-5}\frac{mol}{L}$

Then, according to the law of ideal gases,

$P_{C_{2} H_{4}} = [C_{2} H_{4}]RT = 5.56 x 10^{-5} \frac{mol}{L} x 0.082057 \frac{atm L}{mol K} x 600 K = 2.17x10^{-3} atm$

So, when the partial pressure of ethanol is 200 atm and the partial pressure of water is 400 atm, the partial pressure of ethene at 600 K is 2.17x10⁻³ atm.

7 0

3 years ago

Where do elements in the human body tend to be located on the PERIODIC TABLE? (NOT PERCENTAGES PLEASE)

Ghella [55]

Answer:

Oxygen, Carbon, Hydrogern, Nitrogen, Sulfur, and Chlorine are all non-metals

Calcium, Potassium, Sodium, and Magnesium are all metals

Explanation:

8 0

3 years ago