What do scientists mean when they speak of a phase or state of matter?

Imagine a 10 kg block moving with a velocity of 20/ms to the left calculate the kinetic energy of this block

What is the density of the marble when the mass = 10g

In a system in which the enthalpy changed - 447.1 kJ/mol and the entropy decreases by 75.1 kJ/mol•K, calculate the temperature at which the system will be at equilibrium.

At what temperature will 2.40 moles of chlorine gas exert a pressure of 2.70 atm at a volume of 0.750 L?

You are conducting a weathering study and your solution analysis indicates that you have 1.8 X 10-3 M silica and a pH of 3. You plug this data into your chemical speciation computer program and indicates that quartz precipitates.

Balance the following chemical equation: / text{CH}_ 4 + CH 4 + start text, C, H, end text, start subscript, 4, end subscript, plus / text{O}_ 2 / rightarrow 2 →start text, O, end text, start subscript, 2, end subscript, right arrow / text{CO}_2 +

How did the invention of the spectroscope in 1859 change the science of chemistry

Will zinc and sodium carbonate react?

What fraction of carbon 14 remains in an animal frozen in a glacier 18000 years ago?

How do you convert the number of molecules of a substance to the number of moles? a. add Avogardo's number b. subtract Avogardo's number c. multiply Avogardo's number d. devide Avogardo's number