How does litmus paper identify a base?
a base turns red litmus blue.
a base turns blue litmus red.
a base turns orange litmus red.
a base turns yellow litmus blue.

Answer;

A base turns red litmus blue.

Explanation;

Litmus paper is an acid/base indicator that changes color to identify bases and acids.

Red litmus paper is used in chemical laboratories to identify bases. A base is a substance that accepts hydrogen ions (H+) in water. The color of a red litmus paper remains the same under acidic conditions and turns blue under basic conditions.

Blue litmus paper turns red under acidic conditions and remains the same under basic conditions. An acid is a substance that releases hydrogen ions in an aqueous solution. Blue litmus paper is prepared by treating plain paper with lichen-blue litmus. Blue litmus paper is typically used to test acids, such as sulphuric acid, hydrochloric acid, nitric acid, ethanoic acid, citric acid, and vinegar.

your answer is c) plasma

~*"auba14"*~

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol