List three types of physical evidence that indicate a chemical reaction has occurred

A sample of helium gas occupies a volume of 152.0 mL at a pressure of 717.0 mm Hg and a temperature of 315.0 K. What will the volume be at a pressure of 463.0 mm Hg and a temperature of 777.0 K? The combined gas law equation is given below.

What bonds to cytosine (C) in DNA.

Which molecules shown in the Energy Distribution Graph are likely candidates for evaporation?

How many moles are in 2.3 grams of sulfur

How many moles of water will be generated during the combustion of 0.38 moles of methyl alcohol (CH3OH) ? 2CH3OH + 3O2 2CO2 + 4H2O

A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

Rearrange in to a quadratic 5.333 = (0.6 + 2p) ² / (0.135 - p)

How hot would a 2.3 L balloon have to get to expand to a volume of 3.0 L? Assume the initial temperature of the balloon is 24 °C, and that the pressure inside the balloon remains constant. A. 3 K B. 42 K C. 128 K D. 390 K

Which pair of nitrogen bases will form a bond in a DNA molecule? a. cytosine and adenine b. adenine and thymine c. guanine and thymine d. thymine and cytosine

Most meteors that fall into the earths atmosphere burn up before reaching the ground. Why is this?