Answer:
84.24 g
Explanation:
Given data:
Mass of oxygen = 75 g
Mass of Al required to react = ?
Solution:
Chemical equation:
4Al + 3O₂ → 2Al₂O₃
Number of moles of oxygen:
Number of moles = mass/ molar mass
Number of moles = 75 g/ 32 g/mol
Number of moles = 2.34 mol
Now we will compare the moles of oxygen with Al.
O₂ : Al
3 : 4
2.34 : 4/3×2.34 = 3.12 mol
Mass of Al required:
Mass = number of moles × molar mass
Mass = 3.12 mol × 27 g/mol
Mass = 84.24 g
Answer:
-0.276 Degrees C
Explanation:
kf of water is 1.86
Freezing point depression= m x kf x i
i= ions present ( K+ Cl-) 1=2
1.86x2X.743= .276
Since its freezinf point depression the freezing point will lower
so
0-.276= -.276
Answer:
concrete
2kj for second question
Explanation:
it's gotta be because... let me get back on it.
Answer:
Answer is given below:
Explanation:
<em>Given Data:</em>
mass = 80kg
acceleration = 4 ms
force = 800N
<em>Find out:</em>
friction = ?
<em>Formula</em><em>:</em>
F-friction = weight - f-net
<em>Solution:</em>
weight = (80)(10)
= 800 N
F-net = ma =(80)(4) = 320N
F-friction = weight - F-net
=800 N - 320N
=480N
<em>Answer</em> :
Friction = 480 N
