Which describes the experiments of Becquerel and the Curies? Becquerel showed that uranium requires x-rays to form radiation, and the Curies coined the term “radioactivity.”
Becquerel coined the term “radioactivity,” and the Curies showed that uranium requires x-rays to form radiation.
Becquerel discovered other radioactive elements, and the Curies showed that uranium gave off radioactivity.
Becquerel showed that uranium gave off radioactivity, and the Curies discovered other radioactive elements.

Aroller coaster car is traveling down a track at 22 m/s. the car has a mass of 2000 kg. what is the kinetic energy of the car? a) 22,000 j b) 968,000 j c) 484,000 j d) 44,000 j

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н,о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.