Answer:
278 balloons can be aired.
Explanation:
We apply the Ideal Gases Law to determine the total available volume for each baloon of 0.75L. So we need to divide the volume we obtain by the volume of each baloon.
We determine the moles of CO₂
375 g. 1 mol / 44g = 8.52 moles
V = (n . R . T) / P → (8.52 mol . 0.082 . 298K) / 1 atm = 208.3 L
That's the total volume from the tank, so we can inflate (208.3 / 0.75) = at least 278 balloons
<span>Important information to solve the exercise :
Substance ΔHf (kJ/mol):
HCl(g)= −92.0 </span><span>kJ/mol
Al(OH)3(s)= −1277.0 </span><span><span>kJ/mol
</span> H2O(l)= −285.8 </span><span>kJ/mol
AlCl3(s) =−705.6 </span><span>kJ/mol
</span><span>Al(OH)3(s)+3HCl(g)→AlCl3(s)+3H2O(l)
reactants products
products- reactants:</span><span>
(−705.6) + (3 x −285.8) - ( −1277.0 ) - (3 x −92.0 ) = - 10.0 </span>kJ per mole at 25°C
<span>
</span>
Answer:
Atomic mass = mass of protons + mass of neutrons
Explanation:
In an element atomic mass of an atom can be calculated by adding the mass of protons and neutrons
I hope this helps! :)
Answer:
When <em>a scientist on Earth drops a hammer and a feather at the same time an astronaut on the moon drops a hammer and a feather, the result</em> expected is that <em>the hammer hits the ground before the feather on Earth, and the hammer and feather hit at the same time on the moon (option D).</em>
Explanation:
In the abscence of atmosphere (vacuum), the objects fall in free fall. This is, the only force acting on the objects is the gravitational pull, which is directed vertlcally downward.
Under such absecence of air, the equations that rules the motion are:
- V = Vo + gt
- d = Vo + gt² / 2
- Vf² = Vo² + 2gd
As you see, all those equations are independent of the mass and shape of the object. This explains why <em>when an astronaut on the moon drops a hammer and a feather at the same time</em>, <em>the hammer and feather hit at the same time on the moon</em>, a space body where the gravitational attraction is so small (approximately 1/6 of the gravitational acceleration on Earth) that does not retain atmosphere.
On the other hand, the air (atmosphere) present in Earth will exert a considerable drag force on the feather (given its shape and small mass), slowing it down, whereas, the effect of the air on the hammer is almost neglectable. In general and as an approximation, the motion of the heavy bodies that fall near the surface is ruled by the free fall equations shown above, so, <em>the result </em>that is<em> expected when a scientist on Earth drops a hammer and a feather at the same time is that the hammer hits the ground before the feather</em>.
Physical properties is actually the measure of properties of a substance without producing any changes init. I.e colour, density melting and boling point. While chemical properties shows that either the specific substance will undergo the r/n or not.
So, gasoline is flammable is it’s chemical property.