The horizontal rows in the periodic table are periods, while the vertical rows are called groups. The elements moving from left to right in "periods" have increasing atomic numbers.
Answer:
The sound waves travel from the outer ear and in through the auditory canal, causing the eardrum, or tympanic membrane, to vibrate. This, in turn, causes the three small bones, known as the ossicles, or the hammer, the anvil and the stirrup, in the middle ear to move.
So if they fall, the padding will protect their neck or body part so they will not hit hard against the hard wooden or tile floor.
According to this formula :
ΔTf= i Kf m
i is van't Hoff factor= 1
Kf = 1.86
m the molality we need to assume it
m= x moles of C2H5OH / Kg of mass
∴ 15 = 1 * 1.86 * ( x moles of C2H5OH/ 0.45 kg)
∴X = 3.629 moles
mass = no.of moles x molar mass of C2H5OH
= 3.629 X 46 = 167 g
∴the volume = mass / denisty
= 167 / 0.7893 = 211.57≈ 212 mL
At STP (standard temperature and pressure conditions), 1 mol of any gas occupies 22.4 L
This rule is applied to O₂
22.4 L volume occupied by 1 mol
Therefore 83.4 L occupied by - 1/ 22.4 x 83.4 = 3.72 mol
stoichiometry of O₂ to H₂O is 1:2
then the number of moles of water produced - 3.72 mol x 2= 7.44 mol
mass of water produced - 7.44 mol x 18.01 g/mol = 134.1 g
correct answer is D
