Answer:
I think in the middle of the day because the sun isn't going down yet
Explanation:
Answer: 
Explanation: Because barium is in Group 2, it forms ions with a charge of +2. Fluorine, in Group 17, form ions with a charge of -1. Cross the charges to get the subscripts (Since Ba has a charge of +2, F has a subscript of 2. Because F has a charge of -1, Ba needs a subscript of 1). Therefore, a formula unit of the compound is
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Answer:
Qualitative: Physical observations (the sky is blue, the water is boiling, etc.)
Quantitative: Numberical observations (density= 1 g/ml, volume= 14 ft^3, etc.)
Explanation:
The way to remember it is quaLitative is qualities of the object. QuaNtitative is quantities of the object.
Any factor that causes molecules to collide more frequently speeds up the reaction rate. This is achieved by an increase of the reactants concentration, surface area, raised temp. , raised pressure of gaseous reactant, or an addition of catalysts to the reactant