Tarnish is produced by a redox reaction that occurs when a metal reacts with a nonmetallic compound. The green tarnish on a copper penny might be
produced by a reaction between copper and hydrogen sulfide. What occurs
during this reaction?
A. Hydrogen sulfide acts as an acid, and copper acts as a base.
O B. A double-replacement reaction takes place.
C. Copper atoms gain electrons from sulfur atoms.
D. Copper atoms lose electrons to sulfur atoms.

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd question 6 options: 3000 joules 30 joules 320 joules 3200 joules

An object moves from position +34m to the position -15m in 15 seconds. what is the total displacement? what is the total velocity?

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.