Which of these is true of a chemical reaction

a. Energy is either released or absorbed.

b. Energy is always absorbed.

c. Energy is always released.

d. Energy is not transferred.

What is another name for taxonomy

Luke can paint 91 portraits in 7 weeks. How many portraits can Luke paint in 4 weeks?7

Calculate the standard cell potential at 25 ∘c for the reaction x (s) + 2y + (aq) →x2 + (aq) + 2y (s) where δh∘ = - 793 kj and δs∘ = - 319 j/k. express your answer to three significant figures and include the appropriate

Part a ammonia can be produced via the chemical reaction n2 (g) + 3h2 (g) ⇌2nh3 (g) during the production process, the production engineer determines the reaction quotient to be q = 3.56*10-4. if k = 6.

Bromine (Br,) is observed as a red-brown color During the bromination of benzene, an electrophilic aromatic substitution, why does the red-brown color of Br2 disappear as the reaction progresses? a.

What is the independent and dependent variable for a dry ice experiment

a substance that undergoes a physical change like melting is still the same substance is it true or false

What is a polar molecule

A mixture of He He, N 2 N2, and Ar Ar has a pressure of 22.1 22.1 atm at 28.0 28.0 °C. If the partial pressure of He He is 2475 2475 torr and that of Ar Ar is 1049 1049 mm Hg, what is the partial pressure of N 2 N2?

Oceans make the temperaturs of nearby land more extreme ... True or false