Answer:
70.15 cm³
Solution:
Data Given;
Mass = 55 g
Density = 0.784 g.cm⁻³
Required:
Volume = ?
Formula Used:
Density = Mass ÷ Volume
Solving for Volume,
Volume = Mass ÷ Density
Putting values,
Volume = 55 g ÷ 0.784 g.cm⁻³
Volume = 70.15 cm³
1) The history of egypt is still unclear; artifacts, how the pyramids were built, gods and whatnot.
2) Egypt's history being uncovered in regards to curses and amulets is still being practiced in the country and some others because of the great influence it had.
3) Egyptians being able to construct such grand structures that still stand (pyramids) serves as evidence that proves Egypt was a very advanced civilization at the peak of their advancement.
<h3>
<u>moles of H2SO4</u></h3>
Avogadro's number (6.022 × 1023) is defined as the number of atoms, molecules, or "units of anything" that are in a mole of that thing. So to find the number of moles in 3.4 x 1023 molecules of H2SO4, divide by 6.022 × 1023 molecules/mole and you get 0.5646 moles but there are only 2 sig figs in the given so we need to round to 2 sig figs. There are 0.56 moles in 3.4 x 1023 molecules of H2SO4
Note the way this works is to make sure the units are going to give us moles. To check, we do division of the units just like we were dividing two fractions:
(molecules of H2SO4) = (molecules of H2SO4)/1 and so we have 3.4 x 1023/6.022 × 1023 [(molecules of H2SO4)/1]/[(molecules of H2SO4)/(moles of H2SO4)]. Now, invert the denominator and multiply:
<h3 />
Answer: The bond between boron and hydrogen in boron trihydride is covalent bond.
Explanation:
The type of bonding between the atoms forming a compound is determined by using the electronegativity difference between the atoms. According to the pauling's electronegativity rule:
- If
, then the bond is non-polar. - If
, then the bond will be covalent. - If
, then the bond will be ionic.
We are given:
Electronegativity for boron = 2.0
Electronegativity for hydrogen = 2.1
As, 
is less than 1.7 and not equal to 0. Hence, the bond between boron and hydrogen is covalent bond.
Answer:
H₂SO₄
Explanation:
Given data:
Number of moles of H₂SO₄ = 15 mol
Number of moles of Fe = 13 mol
Which reactant is limiting reactant = ?
Solution:
Chemical equation:
3H₂SO₄ + 2Fe → Fe₂(SO₄)₃ + 3H₂
now we will compare the moles reactant with product.
H₂SO₄ : Fe₂(SO₄)₃
3 : 1
15 : 1/3×15 = 5
H₂SO₄ : H₂
3 : 3
15 : 15
Fe : Fe₂(SO₄)₃
2 : 1
13 : 1/2×13 = 6.5
Fe : H₂
2 : 3
13 : 3/2×13 = 19.5
Number of moles of product formed by H₂SO₄ are less thus it will act as limiting reactant.
