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