All categories

3 years ago

8. Which gas contributes the largest part of air? *

Chemistry

1 answer:

timurjin [86]3 years ago

5 0

Answer:

Nitrogen

Explanation:

Nitrogen present 78% in the earth's atmosphere

You might be interested in

What word best describe chlorophyll

cupoosta [38]

Green.......................................................

6 0

3 years ago

what is the amount of heat,in joules, required to increase the temperature of a 49.5-gram sample of wanted from 22c to 66c

aniked [119]

Answer :

the amount of heat,in joules, required to increase the temperature of a 49.5-gram sample of wanted from 22°c to 66°c is 9.104 Joules.

Explanation:

The answer can be calculated using the formula

Q = mCрΔT

where

Q is the amount of heat required in joules to raise the temperature.

m is the mass of the sample in Kg.

Cp is the specific heat of the sample in J/Kg°C.

ΔT is the change in temperature required.

Here, m = 49.5-gram = 0.0495 kg

Cp = 4.18 J/Kg°C (for water)

T₁ = 22°C ; T₂ = 66°C

ΔT = 66 - 22 = 44

Substituting values in Q = mCрΔT

Q = (0.0495)(4.18)(44)

Q = 9.104 J

5 0

3 years ago

Determine the frequency of radiation whose wavelength is 7.67 x 10^-7 cm. Then, determine the amount of energy in the radiation.

dimulka [17.4K]

Answer:

They frequency = 3.9 * 10^16 Hz

The amount of energy E = 2.58 *10^-17 J

Explanation:

Step 1: Data given

wavelength is 7.67 * 10^-7 cm

Step 2: Calculate the frequency

f = c / λ

⇒ with λ = the wavelength in nm = 7.67 nm

⇒ with c = the speed of light = 3.00 * 10^8 m/s

⇒ f = the frequency = TO BE DETERMINED

f = (3.00 * 10^8 m/s) / 7.67 * 10^-9 m

f = 3.9 * 10 ^16 /s = 3.9 * 10^16 Hz

They frequency is 3.9 * 10^16 Hz

Step 3: Calculate the amount of energy

E = h *f

⇒ with E = the amount of energy (in joule)

⇒ h = Planck's constant = 6.626 *10^-34 J*s

⇒ with f = the frequency

E = 6.626 *10^-34 J*s * 3.9 * 10^16 Hz

E = 2.58 *10^-17 J

8 0

3 years ago

Helium gas collected at a pressure of 0.0045 atm is put into a flexible balloon measuring 350 mL in volume. What volume, in mL,

NISA [10]

Answer: 0.25 atm
Evidence: i looked it up

6 0

3 years ago

CaC2(s) + 2H2O(l) --> Ca(OH)2(aq) + C2H2(g) In the reaction above, 0.5487 grams of calcium carbide are completely consumed to

jasenka [17]

Answer:

239.7mL

Explanation:

Using the general gas equation;

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas constant (0.0821 Latm/molK)

T = temperature (K)

The balanced chemical equation in this question is as follows:

CaC2(s) + 2H2O(l) --> Ca(OH)2(aq) + C2H2(g)

From the equation, 1 mole of CaC2 produces 1 mole of ethylene gas, C2H2.

Using mole = mass/molar mass

Molar mass of CaC2 = 40 + 12(2)

= 40 + 24

= 64g/mol

mole = 0.5487/64

mole = 0.00857mol of CaC2

Hence, 0.00857mol of CaC2 produced 0.00857mol of C2H2

Based on the information provided, n = 0.00857mol, T = 43°C = 43 + 273 = 316K, p = 0.926 atm

PV = nRT

V = nRT/P

V = 0.00857 × 0.0821 × 316/0.926

V = 0.222/0.926

V = 0.2397L

In mL, volume = 0.2397 × 1000

= 239.7mL

3 0

3 years ago