Gd-148 is a radioactive isotope that decays by alpha emission. Each alpha particle emitted carries 5.10E-13 J of kinetic energy. A 80.0 kg worker is accidentally exposed to a sample of Gd-148 having an activity of 0.0500 curies for a total of 5.00 minutes. During that time the workers body absorbs 5.00 percent of the alpha particles emitted by the sample. How many alpha particles were emitted by the sample during the time of the workers exposure

Ethanol (c2h5oh) is produced from the fermentation of sucrose in the presence of enzymes. c12h22o11(aq) + h2o(g) 4 c2h5oh(l) + 4 co2(g) determine the theoretical yield and the percent yields of ethanol if 680. g sucrose undergoes fermentation and 326.5 g ethanol is obtained. theoretical _ g _ percent %

Consider the story you just read. all but one of the choices below indicate that something is living.

Cryolite, na3alf6(s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. start this question by first balance the chemical equation.1.) balance the equation: - alo3(s)+naoh(l)+hf(> na3alf6+h2o(g). 2.) if 17.5 kilograms of al2o3(s), 51.4 kilograms of naoh(l), and 51.4 kilograms of hf(g) react completely, how many kilograms of cryolite will be produced? 3.)which reactants will be in excess, (al2o3, naoh, or hf) 4.)what is the total mass of the excess reactants left over after the reaction is complete in kg?