A student obtained the following data for the decomposition of hydrogen peroxide in dilute sodium hydroxide at 20 °C. H2O2(aq)H2O(l) + ½ O2(g) [H2O2], M 4.90×10-2 2.45×10-2 1.23×10-2 6.15×10-3 time, min 0 7.61 15.2 22.8 (1) What is the half-life for the reaction starting at t=0 min? min What is the half-life for the reaction starting at t=7.61 min? min Does the half-life increase, decrease or remain constant as the reaction proceeds? (2) Is the reaction zero, first, or second order? (3) Based on these data, what is the rate constant for the reaction? min-1

How does a scientist the government? a. the scientist tells people in society what to do. b. the scientist determines the policies that the government spends money on. c. the scientist provides unbiased information to the government. d. the scientist makes laws based on his or her research results.

Astudent made the lewis dot diagram of a compound as shown. mg is written with two dots shown on its top. an o is written on each side of mg. each o has six dots around it. an arrow is shown from one dot on mg toward the vacant space around the o on the right. another arrow is shown from the other dot on mg toward the vacant space around the o on the left. the title of the art is students lewis dot model. what is the error in the lewis dot diagram? an o atom should transfer all its six electrons to mg because the formula is mgo. both electrons of mg should be transferred to one o atom because the formula is mgo. the electrons should be transferred from each o atom to mg because mg has fewer electrons. the number of dots around mg should be four because it has to transfer two electrons to each o.

Ajar is tightly sealed at 22°c and 772 torr what is the pressure inside a jar after its been heated to 178°c