What type of physical change is it when a liquid turns into a solid and a solid turns into a liquid

An unknown gas effuses at 0.850 times the effusion rate of nitrogen dioxide, NO2. Estimate the the molar mass of the unknown gas

The nucleus of an atom ok K-42 contains

Solar homes often use water to collect heat from the sun. If the same amount of heat was used on 2500 kg of water in one house and 1500 kg of water in a second house, what will happen? The 2500 kg of water will reach a higher temperature.

Look at the equation below. O2 + CS2 → CO2 + SO2 Which of the following shows the equation balanced? A. 3 O2 + CS2 → CO2 + 2 SO2 B. 3 O2 + CS2 → 2 CO2 + SO2 C. O2 + CS2 → CO2 + SO2 D. 4 O2 + 4 CS2 → 4 CO2 + 4 SO2

What is the molecular formula of the compound with a molecular weight of 112 g/mol and percent composition: 85.6% c and 14.4 % h

Biofuel is any fuel that is produced from living or once living matter in a short period of time, days, weeks, or even months.

How are revolution and year related

Read the scientific question below. "Does sunlight make plants live?" What is a likely hypothesis for the question?

A chemist is using a solution of HNO3 that has a pH of 3.75. What is [H+] for the solution?

What is the oxidation number for CO2