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2 years ago

I WILL MARK YOU BRAINLIST PLEASE HELP

Chemistry

1 answer:

tekilochka [14]2 years ago

7 0

Answer: See below

Explanation: a. The mass of an element is composed of:

protons: 1 amu each

neutrons: 1 amu each

electrons: 0 amu each

Only the protons and neutrons are counted in the atomic mass of an element

b. Electrons are assigned a mass of 0. They do have a mass, but it is exceedingly small compared to the protons and neutrons, so they are left out of the calculation of an element's mass.

c. An element becomes unstable if the neutrons exceed the protons by a certain ratio, dependent on the element.

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a 2.7 L of N2 is collected at 121kpa and 288 K . if the pressure increases to 202 kpa and the temperature rises to 303 K , what

jok3333 [9.3K]

Answer:

The gas will occupy a volume of 1.702 liters.

Explanation:

Let suppose that the gas behaves ideally. The equation of state for ideal gas is:

$P\cdot V = n\cdot R_{u}\cdot T$ (1)

Where:

$P$ - Pressure, measured in kilopascals.

$V$ - Volume, measured in liters.

$n$ - Molar quantity, measured in moles.

$T$ - Temperature, measured in Kelvin.

$R_{u}$ - Ideal gas constant, measured in kilopascal-liters per mole-Kelvin.

We can simplify the equation by constructing the following relationship:

$\frac{P_{1}\cdot V_{1}}{T_{1}} = \frac{P_{2}\cdot V_{2}}{T_{2}}$ (2)

Where:

$P_{1}$ , $P_{2}$ - Initial and final pressure, measured in kilopascals.

$V_{1}$ , $V_{2}$ - Initial and final volume, measured in liters.

$T_{1}$ , $T_{2}$ - Initial and final temperature, measured in Kelvin.

If we know that $P_{1} = 121\,kPa$ , $P_{2} = 202\,kPa$ , $V_{1} = 2.7\,L$ , $T_{1} = 288\,K$ and $T_{2} = 303\,K$ , the final volume of the gas is:

$V_{2} = \left(\frac{T_{2}}{T_{1}} \right)\cdot \left(\frac{P_{1}}{P_{2}} \right)\cdot V_{1}$

$V_{2} = 1.702\,L$

The gas will occupy a volume of 1.702 liters.

6 0

3 years ago

Which color of visible light has the highest energy?

DanielleElmas [232]

Answer:

Blue: Because violet really has the most and blue is based on violet!

Explanation:

Hope this helps! Plz mark as brainliest!

4 0

3 years ago

Someone answer this please...

boyakko [2]

Answer:

120 mol Mg

General Formulas and Concepts:

Chemistry - Stoichiometry

Using Dimensional Analysis

Explanation:

Step 1: Define

120 moles H₂

Step 2: Identify Conversions

RxN: 3 mol H₂ = 3 mol Mg

Step 3: Stoichiometry

$120 \ mol \ H_2(\frac{3 \ mol \ Mg}{3 \ mol \ H_2} )$ = 120 mol Mg

7 0

3 years ago

Read 2 more answers

For the reaction A (g) → 2 B (g), K = 14.7 at 298 K. What is the value of Q for this reaction at 298 K when ∆G = -20.5 kJ/mol?

harina [27]

Answer:

Q= 245 =2.5 * 10^2

Explanation:

ΔG = ΔGº + RTLnQ, so also ΔGº= - RTLnK

R= 8,314 J/molK, T=298K

ΔGº= - RTLnK = - 6659.3 J/mol = - 6.7 KJ/mol

ΔG = ΔGº + RTLnQ → -20.5KJ/mol = - 6.7 KJ/mol + 2.5KJ/mol* LnQ

→ 5.5 = LnQ → Q= 245 =2.5 * 10^2

6 0

4 years ago

What is the mass in grams of 0.700 moles of water, H2O

irga5000 [103]

Answer:

12.6

Explanation:

$no \: of \: mole= \frac{mass}{molar \: mass}$

0.7=mass/(2+16)

8 0

3 years ago