Ice floats because it is about 9% less dense than liquid water. ... The heavier water displaces the lighter ice, so ice floats to the top. One consequence of this is that lakes and rivers freeze from top to bottom, allowing fish to survive even when the surface of a lake has frozen over
Answer:
b) sharpening a pencil
Explanation:
If you melt lead, boil water, or dissolve sugar in water, you can return all of them back to their original state. If you sharpen a pencil, you can't reattach the shavings as they were originally.
Answer:
option A= Physical change
Explanation:
physical change:
" It is a change in which no new substance is formed"
Breaking of object like glass is the example of physical change because it is not change into another object. It effect the form of object but can not change the chemical composition.
Chemical changes:
" it is a change in which one substance is converted into new product through chemical reaction".
During the chemical changes the types and the number of atom remain same but their arrangement changed.
for example: burning of wood, baking of cake, digesting food, resting of iron etc.
Physical reaction:
" physical reaction occur during the molecular rearrangement. There is no chemical change occur"
In this type of changes no bonds are break to form new bonds, for example boiling point.
Chemical reaction:
" chemical reaction occur when molecules are chemically react with each others and bonds formation and breaking is also occur"
Answer:
The answer is C. The partial pressure of hydrogen will be unchanged.
Explanation:
⇒ 
Argon with electronic configuration 
(that is atomic number 18) is an inert gas making it unreactive and it's addition to the reaction has no effect on the partial pressure of either the reactant or production or the state of the system.
The partial pressure of hydrogen will remain unchanged on the addition of Argon.
<h3>Answer:</h3>
36 moles of Hydrogen
<h3>Solution:</h3>
The molecular formula of Glucose is,
C₆H₁₂O₆
As clear from molecular formula, each mole of Glucose contains 12 moles of Hydrogen atoms.
Therefore,
1 mole of C₆H₁₂O₆ contains = 12 moles of Hydrogen
So,
3.0 moles of C₆H₁₂O₆ will contain = X moles of Hydrogen
Solving for X,
X = (3.0 mol × 12 mol) ÷ 1 mol
X = 36 moles of Hydrogen
