$CATEGORY: Science - Khan Academy/2.Acids, Bases and Salts/2.Acids, Bases and Salts--how strong are acid or base solutions

//Multiple Choice

What does the "H" in pH stand for?
{
= Hydrogen
~ Helium
~ Hydroxide
~ Heat
}

On the pH scale, a pH value less than 7 indicates\:
{
~ Neutral
= Acidic
~ Basic
~ Alkaline
}

What pH value is considered neutral?
{
~ 0
= 7
~ 10
~ 14
}

Which of the following is highly acidic?
{
~ Soap
= Battery acid
~ Sea water
~ Milk
}

Which pH value represents something highly basic?
{
~ 0
~ 3
~ 7
= 14
}

Which of these everyday substances is acidic?
{
= Lemon juice
~ Soap
~ Bleach
~ Sea water
}

What property is associated with basic substances?
{
~ Sour taste
~ Sharp smell
= Slimy texture
~ Neutral color
}

What happens to the body if the blood pH moves too far from neutral?
{
~ Nothing changes
= It can cause serious health problems
~ It improves digestion
~ It becomes more alkaline
}

By what factor does acidity or basicity change when moving by one level on the pH scale?
{
~ 2
~ 5
= 10
~ 100
}

If a substance has a pH of 4 and another has a pH of 8, how much more acidic is the first substance?
{
~ 4 times
~ 10 times
~ 100 times
= 10,000 times
}

Highly basic substances like bleach have a\:
{
= Bitter taste
~ Sour taste
~ Neutral reaction
~ Sweet smell
}

What is the approximate pH of sea water?
{
= Neutral
~ Strongly acidic
~ Strongly basic
~ Highly reactive
}

Why are extreme pH substances dangerous to handle?
{
~ They are slippery
= They are highly reactive
~ They are odorless
~ They evaporate quickly
}

//True or False

The pH scale ranges from 0 to 10. {F}

Substances with a pH value greater than 7 are considered basic. {T}

Lemon juice is highly basic. {F}

A substance with a pH of 7 is neutral. {T}

The pH scale is linear, meaning each step is equal. {F}

Battery acid is an example of a neutral substance. {F}

The term "alkaline" refers to acidic substances. {F}

Blood pH levels moving away from neutral can cause serious health issues. {T}

Sea water is highly acidic. {F}

//Fill in the blanks

The pH scale ranges from ________.
{
~ 0 to 7
~ 7 to 14
= 0 to 14
~ 1 to 10
}

The term "alkaline" refers to ________ substances.
{
~ Acidic
= Basic
~ Neutral
~ Bitter
}

The pH scale is ________, meaning that each step represents a factor of 10.
{
= Logarithmic
~ Linear
~ Circular
~ Non-mathematical
}

Lemon juice is ________ on the pH scale.
{
~ Basic
~ Neutral
= Acidic
~ Alkaline
}

Highly acidic substances have a ________ taste.
{
~ Bitter
= Sour
~ Sweet
~ Slimy
}

Highly basic substances feel ________ to the touch.
{
~ Rough
= Slimy
~ Sticky
~ Neutral
}

The pH of blood is approximately ________.
{
~ 1
= 7
~ 14
~ 4
}

________ substances can cause damage due to their high reactivity.
{
~ Neutral
= Extreme pH
~ Alkaline
~ Mildly acidic
}

//Numericals



//Match the following

Match the following items from Column A with their correct corresponding options from Column B\:
{
=pH of 7 -> Blood (Neutral)
=Battery acid -> Highly acidic
=Liquid drain cleaner -> Highly basic
=Lemons -> Sour taste
=Alkaline -> Arabic Origin
=Milk -> Slightly acidic
}


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