Extract containing benzylpenicilin were prepared for analysis in buffer at pH 6.5 at 25degree Celsius. What is the maximum length of time the solution cam be stored before analysis so that no more than 1% decomposition occurs if rate constant is 1.7×10-7s.

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

Joan writes four numbers on the board in standard form, and then she writes their scientific notation