Answer: The density of the object will be 
Explanation:
Density is defined as the mass contained per unit volume.

Given : Mass of object = 19.6 grams
Volume of object= 
Putting in the values we get:

Thus density of the object will be 
Answer:
120g
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
Sn + 2HF —> SnF2 + H2
Next, we shall determine the number of mole of HF needed to react with 3 moles of Sn.
From the balanced equation above, 1 mole of Sn reacted with 2 moles of HF.
Therefore, 3 moles of Sn will react with = 3 x 2 = 6 moles of HF.
Finally, we shall convert 6moles of HF to grams
This is illustrated below:
Number of mole of HF = 6moles
Molar Mass of HF = 1 + 19 = 20g/mol
Mass of HF =..?
Mass = number of mole x molar Mass
Mass of HF = 6 x 20
Mass of HF = 120g
Therefore, 120g of HF is needed to react with 3 moles of Sn
Answer:
0.0123 moles
Explanation:
Concentration = Moles / Volume of solution
or you can rearrange the formula to get
Moles = concentration (moles/liter) x volume of solution (liter)
First convert your volume to L instead of mL. 35mL = 0.035L
moles = 0.350 moles/liter x 0.035 liter (liters cancel out)
moles = 0.0123
2K + Br2 ===> 2KBr
It's very ionic. The transfer of 2 electrons from K to Br2 is nearly as complete as it can be.