Answer:
n₁ = 1.0× 10⁻⁴ mol
Explanation:
Given data:
Initial volume of balloon = 230 mL
Initial number of moles of He =?
Final number of moles of He = 3.8 × 10⁻⁴ mol
Final volume of balloon = 860 mL
Solution:
The given problem will be solve through Avogadro law,
"Number of moles of gas and volume are directly proportional to each other at constant temperature and constant pressure"
Mathematical relationship:
V₁/n₁ = V₂/n₂
No we will put the values.
230 mL /n₁ = 860 mL/ 3.8 × 10⁻⁴ mol
n₁ = 230 mL× 3.8 × 10⁻⁴ mol/ 860 mL
n₁ = 874 × 10⁻⁴ mol. mL / 860 mL
n₁ = 1.0× 10⁻⁴ mol
Answer: combustion
Explanation:
Combustion reactions can be identified by looking at the reactants and the products.
Usually, the reactants will be a hydrocarbon and oxygen. And the products will be CO2 and H2O
Answer:
Your strategy here will be to use the molar mass of potassium bromide,
KBr
, as a conversion factor to help you find the mass of three moles of this compound.
So, a compound's molar mass essentially tells you the mass of one mole of said compound. Now, let's assume that you only have a periodic table to work with here.
Potassium bromide is an ionic compound that is made up of potassium cations,
K
+
, and bromide anions,
Br
−
. Essentially, one formula unit of potassium bromide contains a potassium atom and a bromine atom.
Use the periodic table to find the molar masses of these two elements. You will find
For K:
M
M
=
39.0963 g mol
−
1
For Br:
M
M
=
79.904 g mol
−
1
To get the molar mass of one formula unit of potassium bromide, add the molar masses of the two elements
M
M KBr
=
39.0963 g mol
−
1
+
79.904 g mol
−
1
≈
119 g mol
−
So, if one mole of potassium bromide has a mas of
119 g
m it follows that three moles will have a mass of
3
moles KBr
⋅
molar mass of KBr
119 g
1
mole KBr
=
357 g
You should round this off to one sig fig, since that is how many sig figs you have for the number of moles of potassium bromide, but I'll leave it rounded to two sig figs
mass of 3 moles of KBr
=
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
360 g
a
a
∣
∣
−−−−−−−−−
Explanation:
<em>a</em><em>n</em><em>s</em><em>w</em><em>e</em><em>r</em><em>:</em><em> </em><em>3</em><em>6</em><em>0</em><em> </em><em>g</em><em> </em>
Ammonia has a characteristic sharp, choking smell. It also makes damp red litmus paper turn blue. Ammonia forms a white smoke of ammonium chloride when hydrogen chloride gas, from concentrated hydrochloric acid, is held near it.
