How many sig figs 18.01528

If you wanted to find a sample of fermium, which has an atomic number 100, where would you look?

sergeinik [125]

The answer would be B: In the Earth’s atmosphere!.

Hope this helps,

7 0

2 years ago

Given the balanced equation representing a reaction: 2h2o(l) + 571.6 kJ -> 2h2(g) + o2(g). What occurred as a result of this

Ivan

Answer: option D) energy was absorbed and entropy increased.

Explanation:

1) Given balanced equation:

2H₂O (l) + 571.6 kJ → 2 H₂ (g) + O₂(g).

2) Being the energy placed on the side of the reactants means that the energy is used (consumed or absorbed). This is an endothermic reaction.

So, the first part is that energy was absorbed.

3) As for the entropy, it is a measure of the disorder or radomness of the system.

Since, two molecules of liquid water were transformed into three molecules of gas, i.e. more molecules and more kinetic energy, therefore the new state has a greater degree of radomness, is more disordered, and you conclude that the entropy increased.

With that, you have shown that the right option is D) energy was absorbed and increased.

7 0

3 years ago

Create a chemical equation for "Bubbling chlorine gas through a solution of sodium bromide gives elemental bromine and a solutio

Alexxandr [17]

Answer:

$Cl_{2} +2NaBr ---> 2NaCl + Br_{2}$

Explanation:

5 0

2 years ago

What is the number of moles in 500L of He gas at STP

kompoz [17]

Ah, this is actually a fairly simple chemistry question.

Recall that at STP, one mole is equivalent to 22.4 L. Knowing this, all you have to do is divide 500 L by 22.4 L to find the number of moles:

500/22.4 = 22.3 mol

-T.B.

7 0

2 years ago

Urea, (NH2)2CO, is a product of metabolism of proteins. An aqueous solution is 37.2% urea by mass and has a density of 1.032 g/m

Feliz [49]

Answer:

The molarity of urea in this solution is 6.39 M.

Explanation:

Molarity (M) is <em>the number of moles of solute in 1 L of solution</em>; that is

$molarity = moles of solute ÷ liters of solution$

To calculate the molality, we need to know the number of moles of urea and the volume of solution in liters. We assume 100 grams of solution.

Our first step is to calculate the moles of urea in 100 grams of the solution,

using the molar mass a conversion factor. The total moles of 100g of a 37.2 percent by mass solution is

60.06 g/mol ÷ 37.2 g = 0.619 mol

Now we need to calculate the volume of 100 grams of solution, and we use density as a conversion factor.

1.032 g/mL ÷ 100 g = 96.9 mL

This solution contains 0.619 moles of urea in 96.9 mL of solution. To express it in molarity, we need to calculate the moles present in 1000 mL (1 L) of the solution.

0.619 mol/96.9 mL × 1000 mL= 6.39 M

Therefore, the molarity of the solution is 6.39 M.

4 0

2 years ago