A substance turns the Universal Indicator bright red. What does this "indicate"?
It is very acidic.
Acids have a pH of _____ than __.
less than 7
Alkalis turn litmus paper ______.
blue
What adjective is the opposite of "concentrated"?
dilute
Metals form oxides that are solids. If they dissolve in water, these oxides give _______ solutions.
alkaline
A substance contains an excess of H+ ions. What is its pH?
It is acidic, so it is lower than 7.
What adjective means "can eat through material"
corrosive
How can we use litmus paper to test the pH of gases?
The litmus paper must be damp.
Acids turn litmus paper _____.
red
The more acidic the solution, the ______ the pH.
lower
What kind of acid is in the atmosphere of Venus?
sulphuric acid (due to volcanic activity)
What does "pH" actually stand for, anyway?!?!
The German "potenz H(ydrogen)", which means the power of the hydrogen-ion concentration.
What is the most accurate method to measure pH?
Use a pH meter which uses an electrode to measure pH electrically.
What adjective is the opposite of "dilute"?
concentrated
Alkalis have a pH _________ than __.
greater than 7
Which acid is present in orange juice?
citric acid
What acid is present in vinegar?
acetic acid (ethanoic acid)
What is an OH- ion called?
a hydroxide ion
Universal Indicator is green in the presence of a substance. What does this indicate?
The substance is neutral.
Name a pH indicator other than litmus or Universal Indicator.
methyl orange or phenolphthalein (also hydrangea flowers, turmeric, and anthocyanins)
Non-metals generally form _______ oxides that dissolve in water to form _______ solutions.
acidic
A substance contains an excess of OH- ions. What is its pH?
It is alkaline, so it is higher than 7.