An element is all the same thing. Pure, if you will.
The first one is definitely an element. The second would be a compound (it's atoms are different colors). I would say the last one is an element, since it has ll the same color of atoms.
I hope this helped you! If you have anymore questions, feel free to ask me.
Answer: Solids
Explanation:
In the solid state, the individual particles of a substance are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles. As a result, solids have a definite shape and volume.
Answer:
179Kj/mol
Explanation:
The equation for the reaction is:
CaO + 3C ⇒ CaC₂ + CO
₂
The formula for calculating the heat absorbed is:
∆Hf (Products) - ∆Hf (Reactants)
Using the heat of formation (∆Hf) for each component in the reaction
∆Hf Cao = -635kj/mol
∆Hf C = 0kj/mol
∆Hf CaC2 = -63kj/mol
∆Hf CO2 = -393.5
The heat absorbed = ( -63 + -393.5) – (-635)
= - 456 + 635
= 179kj/mol
Answer:
Any object will stay in motion unless an output force acts on the object.
Any object will stay in rest unless an output force acts on an object.
Explanation: