Answer:
D.) 4
Explanation:
Al + 3 O₂ --> 2 Al₂O₃
In the equation, there are:
<em>Reactants:</em> 1 Al and 6 O
<em>Products:</em> 4 Al and 6 O
To determine how many atoms there are of each, you multiply the coefficients by the subscripts attached to the atoms. While the question doesn't ask, as you can see, the oxygen atoms are balanced because there is an equal amount on both sides. To balance the aluminum atoms, you can get 4 aluminum atoms on the reactants side by using a coefficient of 4.
The new equation would look this this:
4 Al + 3 O₂ --> 2 Al₂O₃
There are now:
<em>Reactants:</em> 4 Al and 6 O
<em>Products:</em> 4 Al and 6 O
Answer:
Therefore the density of the sheet of iridium is 22.73 g/cm³.
Explanation:
Given, the dimension of the sheet is 3.12 cm by 5.21 cm.
Mass: The mass of an object can't change with respect to position.
The S.I unit of mass is Kg.
Weight of an object is product of mass of the object and the gravity of that place.
Density: The density of an object is the ratio of mass of the object and volume of the object.
[S.I unit of mass= Kg and S.I unit of m³]
Therefore the S.I unit of density = Kg/m³
Therefore the C.G.S unit of density=g/cm³
The area of the sheet is = length × breadth
=(3.12×5.21) cm²
=16.2552 cm²
Again given that the thickness of the sheet is 2.360 mm =0.2360 cm
Therefore the volume of the sheet is =(16.2552 cm²×0.2360 cm)
=3.8362272 cm³
Given that the mass of the sheet of iridium is 87.2 g.
=22.73 g/cm³
Therefore the density of the sheet of iridium is 22.73 g/cm³.
Answer:
35.42g
Explanation:
LiOH + KCI → LiCl + KOH
Let us determine the molar mass of LiOH and LiCl. This is illustrated below:
Molar Mass of LiOH = 7 + 16 + 1 = 24g/mol
Molar Mass of LiCl = 7 + 35.5 = 42.5g/mol.
Now, we can obtain the theoretical yield of LiCl as follow:
From the equation above,
24g of LiOH reacted to produce 42.5g of LiCl.
Therefore, 20g of LiOH will react to produce = (20 x 42.5)/24 = 35.42g of LiCl.
From the above calculations, the theoretical yield of LiCl is 35.42g
Explanation:
S= 2
P=6
D=10
F= 14
F orbital holds a maximum of 14 electrons
Answer:
The mass percent of carbon in C₁₄H₁₉NO₂ is 72.1%.
Explanation:
To calculate the mass percent of carbon in C₁₄H₁₉NO₂ we have to follow two simple steps:
1st) Look for the atomic weight of each element in the Periodic Table and then multiply each one by its subscript in the molecule and finally sum all of them to find the molar weight of the molecule:
Carbon atomic weight . Carbon subscript = 12 . 14 = 168g
Hydrogen atomic weight . Hydrogen subscript = 1 . 19 = 19g
Nitrogen atomic weight . Nitrogen subscript = 14 . 1 = 14g
Oxygen atomic weight . Oxygen subscript = 16 . 2 = 32g
The molar weight of C₁₄H₁₉NO₂ is: 168g + 19g + 14g +32g = 233g.
2nd) Find the mass percent of carbon with a Rule of three:
If 233g represents the 100% of mass, the 168g of carbon in the molecule will represents the 72.1% of mass.
The Rule of three is:
233g ------------- 100%
168g ------------- = (168 . 100)/233 = 72.1% mass of carbon.
