In terms of energy, how would you classify the following chemical reaction?

2Cu + O2 + 315 KJ---> 2CuO A. endothermic

B. exothermic

C. both endothermic and exothermic

D. Neither endothermic nor exothermic

A body has density of 2kg/m² and volume 2m². Find the mass of the volume

Light is incident on a lens with a thin coating. The light first travels through the thin coating, and then the lens. The thin coating has an index of refraction of n = 1.3, and the lens has an index of refraction of n=1.6.

If a ball rolls off a 4m high table at 7m/s, how long will it take until it hits the floor

Quando e como surgiu a ginastica rítmica no mundo e no Brasil?

Cosmic ray particles can do permanent damage to DNA, especially if both strands are damaged. Explain why damage to just one base on one strand of a DNA molecule may be repairable.

A flash of white light containing all the colors of the visible spectrum in air shines straight down on the surface of a pool.

A car accelerates uniformly from 0 to 15m/s in 5 s. Calculate acceleration.

Which device would a sleep researcher use to monitor a sleeping person's brain waves?

An experiment is performed to obtain the value of a physical property. If the true (i. e., correct) value of the property is 50 and the measured (i. e., experimental) value is 32, the percent error of the experimental result is:

White moths were found in huge numbers in the city of Birmingham. These moths could be easily camouflaged by the trees. Because of sudden industrial development, the trees in the city were covered with soot.