Where is energy stored in living sytems

If 8.6 L of O2 reacted with excess H2 at STP, what is volume of the gaseous water collected? @h2 (g) + O2 (g) = 2H2 O (g)

LekaFEV [45]

Note that this is occurring at STP, where 22.4L of any gas is equal to 1mol of that gas.

First, convert the liters of O₂ to moles of O₂ using the conversion factor 22.4LO₂ = 1molO₂.
8.6LO₂ × 1molO₂/22.4LO₂
= 8.6/22.4
≈ 0.3839molO₂

Next, convert moles of O₂ to moles of H₂O. In the balanced equation, the coefficients show that there are 2 moles of H₂O for every mole of O₂. So, use the conversion factor 1molO₂ = 2molH₂O.
0.3839molO₂ × 2molH₂O/1molO₂
= 0.3839 × 2
= 0.7678molH₂O

Finally, convert the moles of H₂O to liters of H₂O using the same conversion factor from before, 22.4LH₂O = 1molH₂O.
0.7678molH₂O × 22.4LH₂O/1molH₂O
= 0.7678 × 22.4
≈ 17LH₂O

So, the answer is 17 liters of gaseous water is collected! Note that its rounded to 17 because the measurement given in the problem has 2 sig figs. Hope that helps! :)

3 0

4 years ago

- How many grams are in 4.6 x 1016 molecules of phosphorus trichloride (PCI)?

MariettaO [177]

Answer:

0.0000101 grams.

Explanation:

First of all, use Avogadro's number to convert from molecules to moles.

Avogadro's number is 6.02 x 10^23.

Second of all, to convert from moles to grams, find the substance formula of phosphorus trichloride. After finding the substance formula, then find the molar mass of phosphorus trichloride.

Phosphorus trichloride is PCl3

Now find the molar mass of PCl3

P = 31.0 amu

Cl = 35.5 amu

They are three chlorine atoms and one phosphorus atom. So you do this.

31.0(1) + 35.5(3) = 137.5 g/mol

Now use dimensional analysis to show your work

4.6 x 10^16 grams of PCl3 * 1 mol/ 6.02 x 10^23 * 137.5 g/mol / 1 mol

The grams and the moles cancel out.

So now do [(4.6 x 10^16) / (6.02 x 10^23)] x 137.5

and you will get 0.000010507

4.6 has the fewest digits which is 2.

So use sig figs and the answer rounds to the nearest millionths.

0.000010507 rounds to 0.0000101

So the final answer is 0.0000101 grams(don't forget the units)

Hope it helped!

4 0

3 years ago

A chemist has 2.0 mol of methanol (CH3OH). Molar mass of menthanol is 32.0g/mol. What is the mass, in grams, of the sample

Mademuasel [1]

2.0 mol x 32.0 g / 1 mol =

3 0

3 years ago

Which statement is true for an open system?

Bingel [31]

Answer:

Before we get into the first law of thermodynamics we need to understand the relation between heat and work and the concept of internal energy. Just like mass, energy is always conserved i.e. it can neither be created nor destroyed but it can be transformed from one form to another. Internal energy is a thermodynamic property of the system that refers to the energy associated with the molecules of the system which includes kinetic energy and potential energy.

Whenever a system goes through any change due to interaction of heat, work and internal energy, it is followed by numerous energy transfer and conversions. However, during these transfers, there is no net change in the total energy.

Similarly, if we look at the first law of thermodynamics it affirms that heat is a form of energy. What it means is that the thermodynamic processes are governed by the principle of conservation of energy. The first law of thermodynamics is also sometimes referred to as the Law of Conservation of Energy

Explanation:

3 0

3 years ago

What does nuclear fusion release?

Kisachek [45]

Answer:

Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The difference in mass between the reactants and products is manifested as either the release or absorption of energy

Explanation:

6 0

3 years ago