Answer:
Explanation:
I'll assume 1.49 is liters.
All gases occupy 22.4 L for each mole of gas at STP. This makles a very useful, and important, conversion factor:
(22.4L/mole gas) for all gases at STP.
Therefore 1.49L of H2 would be:
(1.49L H2)/(22.4L/mole gas) = 0.0665 moles
The molar mass of H2 is 2, so:
(0.0665 moles)*(2g/mole) = 0.133 grams to 3 sig figs
Answer:
They display the number of valence electrons surrounding an element or compound.
Explanation:
D because it’s not going into then air or to the clouds
Answer:
A new substance was forming
Explanation:
Two types of changes are undergone by substances involved in a reaction. They are physical changes and chemical changes. Physical changes are those changes that does not involve the synthesis of a new product. On the other hand, CHEMICAL CHANGES alters the chemical composition of the substances involved, and hence, new substances are formed.
Chemical changes are usually characterized by change of temperature, color change, evolution of a gas etc. According to this question, Mia mixed two substances in a test tube and noticed that the test tube became warm. She also noticed gas coming from the test tube. Based on Mia's observations, a CHEMICAL CHANGE, LEADING TO THE FORMATION OF NEW SUBSTANCE, HAS OCCURRED.
C. The formation of precipatation
