How can energy change during a chemical reaction?

a. transfer of heat and/or work

b. increase in heat and/or destruction of matter

c. change in the mass of the reactants or thermal energy

d. increase or decrease in total energy of a system?

A cell membrane consists of an inner and outer wall separated by a distance of approximately 10nm. Assume that the walls act like a parallel plate capacitor, each with a charge density of 10?5C/m2, and the outer wall is positively charged.

Does the distance between two charged objects affect the force of attraction?

Two charges separated by a distance of 1 meter exert a 2-n force on each other. if the magnitude of each charge is doubled, the force on each charge is

How dose an atom become an ion with a - 2 charge?

If workers are allowed a maximum dose of 5.0 rem in 1 year, how close to the source may they operate, assuming a 35-h work week? Assume that the intensity of radiation falls off as the square of the distance.

Which method would you use to find the volume of an irregular shaped object?

A step up transformer has a primary coil with 100 turns and a secondary coil with 25 turns if the input voltage in the primary coil is 40 volts what is the output voltage reduced to in the secondary coil A) 20 volts B) 35 volts C) 4 volts D) 10

An instrument used to measure atmospheric pressure is called a

A 200-kg boulder is 1000-m above the ground. what is its potential energy?

The law of reflection states that if the angle of incidence is 81 degrees, the angle of reflection is ___ degrees.