Answer:
Scientific laws or laws of science are statements, based on repeated experiments or observations, that describe or predict a range of natural phenomena.
Explanation:
hope it's help
Answer:
We need 92.3 grams of sodium azide
Explanation:
Step 1: Data given
Mass of nitrogen gas = 59.6 grams
Molar mass of nitrogen gas = 28.0 g/mol
Molar mass of sodium azide = 65.0 g/mol
Step 2: The balanced equation
2NaN3 → 2Na + 3N2
Step 3: Calculate moles nitrogen gas
Moles N2 = mass N2 / molar mass N2
Moles N2 = 59.6 grams/ 28.0 g/mol
Moles N2 = 2.13 moles
Step 4: Calculate moles NaN3
for 2 moles NaN3 we'll have 2 moles Na and 3 moles N2
For 2.13 moles N2 we need 2/3* 2.13 = 1.42 moles NaN3
Step 5: Calculate mass NaN3
Mass NaN3 = Moles NaN3 * molar mass NaN3
Mass NaN3 = 1.42 moles * 65.0 g/mol
Mass NaN3 = 92.3 grams
We need 92.3 grams of sodium azide
<span>During cooling, the kinetic energy of the molecules falls, be</span>cause, when cooling a substace, the particles (molecules) slow down.
The kinetic energy is related to the speed, such that the lower speed the lower kinetic energy.
Particles can translate and vibrate, in the case of gases and liquids, and only vibrate (in the case of solids).
As a substance is cooled the particles get closer and the motion (translation and vibration), slows down. You can see by the equation of the kinetic energy (KE):
KE = [1/2]mass×(speed)² that as the speed is lower the KE will also be lower.
Additionally, when the cooling does not drive a change of phase (gas to liquid, liquid to solid, or solid to gas), it drives a decrease on temperature. In this case you should know that the temperature is a measure of the kinetic energy: the lower the temperature, the lower the kinetic energy.
A is correct................
To express the answer of (6.93 x 10¹) (2.0 x 10-4) in scientific notation, it should be 1.4 x 10^-2. <span>To </span>multiply<span> two numbers expressed in </span>scientific notation<span>, simply </span>multiply<span> the numbers out front and add the exponents. I hope it helps. </span>
