Explanation:
subscript is K
superscript is ^
subscript K means a unit of temperature like F or C
superscript ^ means to the power of
So all together it means to the power of 40 K
Since the compound has 1.38 time that of oxygen gas at the same conditions of temperature and pressure, we have the relationship:
MW/MWoxygen = 1.38
MW = 44.16
Since there is water formed during the reaction, the formula of the compound must be:
XaHb
where a and b are the coefficients of each element.
If the compound reactions with oxygen forming water and an oxide of the element X, the combustion reaction must be:
XaHb + ((2a + (b/2))/2) O2 = a (XO2) + (b/2)(H2O)
Using dimensional analysis:
10 (1/44.16) (b/2 / 1) (18) = 16.3
Solving for b:
b = 8
The compound now is XaH8. Most probably, the compound is C3H8 since it has a molecular formula of 44 and it reacts with O2 to form water and CO2.
2 Al+ 3 CuO-> 1 Al2O3+ 3Cu
The air molecules in the compressions of the second wave are denser, so the sound is louder.
<h3>What is a sound wave?</h3>
Sound waves are longitudinal waves that travel through a medium like air or water.
In a closed room, Noah and Nina are sitting 15 m apart.
As Noah says the same sentence twice, Nina does not hear the sound the first time but she does hear the sentence the second time.
This happens as the air molecules in the compressions of the second wave are denser. As a result, the sound is louder.
The correct option is ''The air molecules in the compressions of the second wave are denser, so the sound is louder''.
Learn more about the sound wave here:
brainly.com/question/1554319
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