B) ionic bond
(although in reality, every bond is fundamentally the sharing of a pair of electron. but due to unmutal electonegativity, the molecule becomes polar)
Answer:
The US surgeon general's 1964 report declared that smoking cigarettes was linked to cancer .
The average global temperature of the Earth has increased by almost two degrees in the last century.
Explanation:
Science and pseudoscience differs in terms of scientific methods involved in any study. Science deals with the practices and beliefs that undergo a method of scientific study. Pseudoscience is the term associated with the ideas and beliefs that tend to be scientific in nature but they fail in their execution of following the scientific methods.
From the given options, two of them are the examples of science and not pseudoscience.
Answer:
124.56 moles of Hydrogen atoms.
Explanation:
We'll begin by calculating the number of moles of ethane that contains 1.25×10²⁵ molecules. This can be obtained as follow:
From Avogadro's hypothesis, 1 mole of any substance contains 6.02x10²³ molecules. This implies that 1 mole of ethane also contains 6.02x10²³ molecules.
Thus, 6.02x10²³ molecules are present in 1 mole of ethane.
Therefore, 1.25×10²⁵ molecules are present in = 1.25×10²⁵/6.02x10²³ = 20.76
Therefore, 20.76 moles of ethane contains 1.25×10²⁵ molecules.
Finally, we shall determine the number of mole of Hydrogen in 20.76 moles of ethane. This can be obtained as follow:
Ethane has formula as C2H6.
From the formula, 1 mole of ethane, C2H6 contains 6 moles of Hydrogen atoms.
Therefore, 20.76 moles of ethane will contain = 20.76 × 6 = 124.56 moles of Hydrogen atoms.
Therefore, 1.25×10²⁵ molecules of ethane contains 124.56 moles of Hydrogen atoms.
Answer:
Solutions from highest to lowest freezing point:
0.040 m glycerin = 0.020 m potassium bromide > 0.030 m phenol
Explanation:
= Depression in freezing point
i = van'T Hoff fcator
= Molal depression constant of solvent
m = molality of the solution
Higher the value of depression in freezing point at lower will be freezing temperature the solution.
1. 0.040 m glycerin
Molal depression constant of water = 
i = 1 ( organic molecule)
m = 0.040 m
2. 0.020 m potassium bromide
Molal depression constant of water =
i = 2 (ionic)
m = 0.020 m
3. 0.030 m phenol
Molal depression constant of water =
i = 1 (organic)
m = 0.030 m
Solutions from highest to lowest freezing point:
0.040 m glycerin = 0.020 m potassium bromide > 0.030 m phenol
