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3 years ago

Please help me!Will give the brainliest!Please answer correctly.Really urgent!!

Chemistry

1 answer:

Nostrana [21]3 years ago

3 0

Explanation:

1,a: I) group 2 = strontium

ii) chlorine

iii) nitrogen

B) i) strontium outer shell=2

ii)nitrogen:outer shell=5

iii) chlorine=7

C)metal

strontium

nickel

molybdenum

cesium

tin

non metal:..

chlorine

nitrogen

neon

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Which two elements have similar physical and chemical properties?

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Explanation:

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2 years ago

The amount of heat energy required to raise the temperature of a unit mass of a material one degree is

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3 years ago

Be sure to answer all parts.The combustion of a 40.0−g gaseous mixture of H2 and CH4 releases 3766 kJ of heat. Calculate the amo

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Answer:H2=11.4g

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1. CH4 +2O2___CO2+2H2O

2.2H2+O2___2H2O

Combining the two we have CH4 +2H2+3O2___

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3 years ago

A 720. cm^3 vessel contains a mixture of Ar and Xe. If the mass of the gas mixture is 2.966 g at 25.0°C and the pressure is 760.

sleet_krkn [62]

Explanation:

The given data is as follows.

Pressure (P) = 760 torr = 1 atm

Volume (V) = $720 cm^{3}$ = 0.720 L

Temperature (T) = $25^{o}C$ = (25 + 273) K = 298 K

Using ideal gas equation, we will calculate the number of moles as follows.

PV = nRT

Total atoms present (n) = $\frac{PV}{RT}$

= $1 \times \frac{0.720 L}{0.0821 \times 298}$

= 0.0294 mol

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Hence, total number of moles will be as follows.

x + y = 0.0294

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x = 0.0097 mol

y = (0.0294 - 0.0097)

= 0.0197 mol

Therefore, mole fraction will be calculated as follows.

Mol fraction of Xe = $\frac{y}{(x+y)}$

= $\frac{0.0197}{0.0294}$

= 0.67

Therefore, the mole fraction of Xe is 0.67.

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2 years ago

Please help me!Will give the brainliest!Please answer correctly.Really urgent!!​

Please help me!Will give the brainliest!Please answer correctly.Really urgent!!