How do you know when a chemical reaction has taken place?

When 1.0 mole of fe (s) reacts with excess o2 (g) and 0.325 moles of fe2o3 are produced. what is the %yield of fe2o3?

Describe one likely result if the placenta became damaged and could not maintain progesterone levels

A box experiences a force of 2 N to the left and 3 N to the right. Which is true of the box's motion? A) The box will slow down. B) The box's velocity will be 1 m/s. C) The box's velocity will not change. D) The box will experience acceleration.

When carbon undergoes sp2 hybridization it forms

Predict the spontaneity of a reaction (and the temperature dependence of the spontaneity) for each possible combination of signs for? H and? S (for the system).

Which item takes the most amount of water to produce

1. Which of the following two ingredients can combine to make a compound? a. Salt and water b. Hydrogen and oxygen c. Eggs and butter d. Sugar and water 2.

What are two ways climate can influence weathering?

A light has a wavelength of 4.10*10^12m. What is the Frequency?

If a compound has a molar más of 180g/mol and it's empirical formula is CH^2O, what is it's molecular formula?