1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
pantera1 [17]
3 years ago
11

Hydrogen and helium in the universe were formed by which of these phenomena?

Chemistry
1 answer:
baherus [9]3 years ago
5 0
I think the answer is a
You might be interested in
1.00g of a metallic element reacts completely with 300cm3 of oxygen at 298K and 1 atm pressure to form an oxide which contains O
elena55 [62]

Answer:

The metal is most likely calcium which has a molar mass of 40.078 g

<em>Note: The question is incomplete. The complete question is given below:</em>

1.00g of a metallic element reacts completely with 300cm3 of oxygen at 298K and 1 atm pressure to form an oxide which contains O2– ions. The volume of one mole of gas at this temperature and pressure is 24.0dm3 .

What could be the identity of the metal?

<em>A calcium B magnesium C potassium D sodium</em>

Explanation:

Number of moles of the oxygen gas reacted is first determined:

Volume of oxygen gas = 300 cm³ = 0.30 dm³

1 mole of a gas occupies 24.0 dm³ at this temperature and pressure

Number of moles of oxygen gas that will occupy 0.30 dm³ = 0.3/24 = 0.125 moles

Let M be represent the metallic element. The equation of the reaction will be:

2M + O₂ ----> 2MO

From the equation of reaction;

2 moles of the metal reacts with 1 mole of oxygen gas

2 * 0.125 moles of the metal will react with 300 cm³ of oxygen  = 0.025 moles

Since the mass of the metal that reacted with oxygen is 1.0 g, therefore, 1.0 g of the metal = 0.025 moles

mass of 1 mole of the metal = 1 /0.025 = 40.0 g

Therefore, the metal is most likely calcium which has a molar mass of 40.078 g

5 0
3 years ago
How did quantum mechanics change our understanding of atoms
Snowcat [4.5K]
1 Answer. IF we look at the shell model we get a very 2d view , T he quantum mechanics make us realize there is a lot more to realizing the location of an electron. The big change in understanding that happened with Quantum Physics is the idea that the universe is random, rather than clockwork, at its lowest level
4 0
2 years ago
How many joules of heat are required to heat 131.0 grams of room temperature water (22 °C) to the boiling point?
vampirchik [111]

100.0g x 4.184J/g/°C x 78°C ΔT = 32,645.2 Joules.

3 0
3 years ago
One mole of an ideal gas is contained in a cylinder with a movable piston. The temperature is constant at 77°C. Weights are remo
frozen [14]

Answer:

The total work is 4957.45J

Explanation:

For an ideal gas, at constant temperature the definition of work (W) is

W = - P.dV = - n.R.T \int\limits^i_f {\frac{dV}{V} \\W = - n.R.T. Ln (\frac{V_{f}}{V_{I}})\\W = - n.R.T. Ln (\frac{P_{i}}{P_{f}})

where P is the pressure, V the volume, n the moles number, T the temperature and R the gas constant.

To solve the problem is necessary to replace the two steps in the equation

Stape 1: n  = 1 mol, R = 0.082atm.L/K.mol, T = 77ºC = 350K, Pi = 5.50atm and Pf = 2.43atm.

W_{1} = - 1molx0.082\frac{atm.L}{K.mol}x350KxLn (\frac{5.50atm}{2.43atm}) = 23.44atm.Lx101.325\frac{J}{atm.L} =2375.44J

Stape 2: n  = 1 mol, R = 0.082atm.L/K.mol, T = 77ºC = 350K, Pi = 2.43atm and Pf = 1.00atm.

W_{2} = - 1molx0.082\frac{atm.L}{K.mol}x350KxLn (\frac{2.43atm}{1.00atm}) = 25.48atm.Lx101.325\frac{J}{atm.L} =2582.01J

The total work is the sum of the two steps

W = W_{1} + W_{2} = 2375.44J + 2582.01J = 4957.45J

4 0
3 years ago
The boiling point of a liquid is 50°C. What is this temperature on the Kelvin scale?
IceJOKER [234]

Answer:

323.15 or just 323 depending on the teacher

3 0
3 years ago
Read 2 more answers
Other questions:
  • 9. What happens to the thermal energy that is added to the water between 4 and 11 minutes?
    15·1 answer
  • Help!!! I need the answer for "explain how using the periodic table can help answer this question"
    13·1 answer
  • What happens to temperature and kinetic energy of particles during a change of state
    8·1 answer
  • 3 A specific amount of energy is emitted when excited electrons in an atom in a sample of an element return to the ground state.
    5·1 answer
  • A constant-volume calorimeter was calibrated by carrying out a reaction known to release 3.50 kJ of heat in 0.200 L of solution
    12·1 answer
  • A water treatment plant applies chlorine for disinfection so that 10 mg/L chlorine is achieved immediately after mixing. The vol
    11·1 answer
  • How many moles of copper would be needed<br> to make 1 mole of Cu,O?
    14·1 answer
  • ____________ rays show areas where large quantities of energy are released.
    5·1 answer
  • You're going on a plane from Alaska to Florida and you're taking your bike. It's the middle of the winter. You fill up your tire
    15·1 answer
  • Genes are sections of DNA that code for a particular trait. Genes are
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!