1) D = 13.6 g / mL
2)ethyl alcohol weighs 158g
3)ρ
_copper = 8.9 g 
Explanation:
1)
D = m / V
=306.0 g / 22.5 mL
D= 13.6 g / mL
2)
density = mass / volume
mass = density × volume
=0.789g /ml × 200.0 ml
M=158g
Ethyl alcohol weighs 158g
3)
ρ (density) = Mass / Volume
ρ
_copper = 1896 g / 8.4cm × 5.5cm × 4.6cm
= 1896g / 212.5
ρ
_copper=8.9 g
Answer:
3 electrons
Explanation:
aluminum : [Ne]3s23p1 [ N e ] 3 s 2 3 p 1 . It loses 3 electrons from 3s and 3p orbitals and attains the noble gas configuration of Neon.
This equation is balanced
<h3>Answer:</h3>
162.43 g of FeCl₂
<h3>
Explanation:</h3>
Step 1: Calculate mass of Fe;
As,
Density = Mass ÷ Volume
Or,
Mass = Density × Volume
Where Volume is the volume of water displaced = 10.4 mL
Putting values,
Mass = 7.86 g.mL⁻¹ × 10.4 mL
Mass = 81.744 g of Fe
Step 2: Calculate amount of FeCl₂;
The balance chemical equation is as follow,
Fe + 2 HCl → FeCl₂ + H₂ ↑
According to this equation,
55.85 g (1 mol) Fe produced = 110.98 g (1 mol) of FeCl₂
So,
81.744 g Fe will produce = X g of FeCl₂
Solving for X,
X = (81.744 g × 110.98 g) ÷ 55.85 g
X = 162.43 g of FeCl₂
43.8 has 3 significant figures and 1 decimal.
<h3 /><h3>What are significant figures?</h3>
The term significant figures refer to the number of important single digits (0 through 9 inclusive) in the coefficient of an expression in scientific notation.
All zeros that occur between any two non-zero digits are significant. For example, 108.0097 contains seven significant digits. All zeros that are on the right of a decimal point and also to the left of a non-zero digit are never significant. For example, 0.00798 contained three significant digits.
Hence, 43.8 has 3 significant figures and 1 decimal.
Learn more about significant figures here:
brainly.com/question/14359464
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