Answer:
Cretaceous Period
Explanation:
Dinosaurs went extinct about 65 million years ago (at the end of the Cretaceous Period), after living on Earth for about 165 million years.
Answer:
Q = 797.5 cal
Explanation:
Given that,
Mass of iron, m = 50 g
The temperature rises from 55°C to 200°C.
We need to find the heat needed to raise the temperature. The heat raised is given by :
Put all the values,
So, 797.5 calories of heat is needed.
Answer:
30 moles of water will produced.
Explanation:
Given data:
Number of moles of O₂ react = 15 mol
Number of moles of water formed = ?
Solution:
Chemical equation:
2H₂ + O₂ → 2H₂O
Now we will compare the moles of water with oxygen.
O₂ : H₂O
1 : 2
15 : 2×15 = 30 mol
30 moles of water will produced.
Answer:
No, I don't think so at least
Explanation:
In chemistry, you do calculations to find the concentration of a solution with another solution of KNOWN concentration. Without concentrations of either solution, were would you get values from? Where would you start? :3
The answer is: volume of ammonia gas is 7.4 L.
Chemical reaction: 6NO + 4NH₃ → 5N₂ + 6H₂O.
m(NO) = 15 g; mass of nitrogen(II) oxide.
M(NO) = 30 g/mol; molar mass of nitrogen(II) oxide.
V(NH₃) = ?
n(NO) = 15 g ÷ 30 g/mol.
n(NO) = 0.5 mol; amount of nitrogen(II) oxide.
From chemical reaction: n(NO) : n(NH₃) = 6 : 4.
0.5 mol : n(NH₃) = 6 : 4.
n(NH₃) = 0.33 mol; amount of ammonia.
Vm = 22.4 L/mol; molar volume at STP.
V(NH₃) = 0.33 mol · 22.4 L/mol..
V(NH₃) = 7.4 L.
