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3 years ago

Which of the following items are true of early nuclear science?

1 answer:

7 0

The items that are true of early nuclear science are "the first nuclear reactions were done in the 1880s" and "the first nucleus split was uranium-235." The answers are letters A and D. It is impossible that nucleus was lost during the reaction as it will not follow the law of mass conservation.

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Gas and oxygen gas are the _______.

stiv31 [10]

i think it is Synthesis Reaction because in a synthesis reaction one or more simple substances combine to form a more complex substance.

If there is two or more reactions yilding one product is another way to identify a synthesis reaction.

For the chemical equation for this synthesis reaction really looks like:

reactant +reactant = product

if im wrong correct me but have a blessed day/night

4 0

3 years ago

A 1.68 g sample of water is injected into a closed evacuated 5.3 liter flask at 65°C. What percent (by mass) of the water will b

Angelina_Jolie [31]

Answer:

50.4 % of the water will be vapor

Explanation:

Step 1: Data given

Mass of water = 1.68 grams

volume of the flask = 5.3 L

Temperature = 65°C

Vapor pressure of water at 65°C = 187.5 mmHg = 0.2467 atm

Step 2: Calculate moles of H2O

p*V=n*R*T

⇒ p = the pressure of water = 0.2467 atm

⇒ V = the volume of the flask = 5.3 L

⇒ n = moles of water

⇒ R = gas constant = 0.08206 L*atm/ K*mol

⇒ T = the temperature = 65°C = 338 Kelvin

n = (p*V)/(R*T)

n = (0.2467 * 5.3) /(0.08206* 338)

n = 0.047 moles

Step 3: Calculate mass of water

Mass of water = moles of water * molar mass of water

Mass of water = 0.047 moles *18.02 g/mol

Mass of water = 0.84694 grams

Step 4: Calculate the percent of water vaporized

% = (0.84694 grams/1.68 grams) *100%

% = 50.4%

50.4 % of the water will be vapor

5 0

3 years ago

If the pressure on a gas at -73°C is doubled but its volume is held constant, what will its final temperature be in degrees Cels

Gre4nikov [31]

Answer:

127°C

Explanation:

This excersise can be solved, with the Charles Gay Lussac law, where the pressure of the gas is modified according to absolute T°.

We convert our value to K → -73°C + 273 = 200 K

The moles are the same, and the volume is also the same:

P₁ / T₁ = P₂ / T₂

But the pressure is doubled so: P₁ / T₁ = 2P₁ / T₂

P₁ / 200K = 2P₁ / T₂

1 /2OOK = (2P₁ / T₂) / P₁

See how's P₁ term is cancelled.

200K⁻¹ = 2/ T₂

T₂ = 2 / 200K⁻¹ → 400K

We convert the T° to C → 400 K - 273 = 127°C

4 0

3 years ago

Earth is one of the planets in the

prisoha [69]

Answer:

moon obviously

Explanation:

........

6 0

3 years ago

Read 2 more answers

Which of these statements is correct? a. Particles in a suspension will settle out if left undisturbed. b. A solution is heterog

tatuchka [14]

Blood. It is discrete cells in saline solutuion. The cells are free to move thru the plasma, or you wouldn't have blood flow, or oxygenation, and you would die. Blood is defined as liquid, not jello.

The other three are things not normally associated--water will fall from the sky as rain, for example, but is held in suspension in fog. Same with the salad oil in mayo. O.J. can be a suspension; easily separated by a filter, Or a colloid--depends if the pulp, if Any, is held in suspension or not. Usually, pulp will settle to the bottom, making that sample of Orange juice a suspension. At different temperatures, it acts differently. But, so does Fog. A colloid is something that normally shouldn't be as some of its molecules are too dense to normally "float" in suspension. Colloid means "glue".

4 0

3 years ago