Answer:

Explanation:
According to the Law of Conservation of Mass, the mass of the products must equal the mass of the reactants.
- mass products = mass reactants
In this problem, the reaction is:

- The reactants are iron and oxygen. We know the mass of the iron sample is 10 grams.
- The product is ferric oxide. The mass of the ferric oxide sample is 18.2 grams.

We want to find how many grams of oxygen reacted. We have to get the oxygen by itself. 10 is being added to oxygen. The inverse of addition is subtraction. Subtract 10 from both sides of the equation.



<u>8.2 grams of oxygen </u>reacted with 10 grams of iron to form 18.2 grams of ferric oxide.
Answer:
CaCO3 is false
Explanation:
Because HCl is hydrongen chloride
Answer:
An element
It stays shiny
Explanation:
Pure Gold is an element.
An element is a distinct substance that cannot be split-up into simpler substances. Such substances consists of only one kind of atom.
There are over a hundred elements known to date.
As an element, Gold is classified as a metal due to its very unique set of properties.
One of the indicator that gold does not react with oxygen is that it stays shiny. It does not give rusty look when exposed to air.
Substances that combines with oxygen have a rusty look or change appearance when expose to air. For example, iron.
Answer:
High temperature and low pressure
Explanation:
According to the kinetic molecular theory, gases are composed of small particles called molecules which are in constant motion.
At high temperature and low pressure, gas molecules possess high kinetic energy and move at high velocities hence intermolecular interaction is almost none existent and real gases approach the behavior of ideal gases.