Answer:
A
Explanation:
THAT'S THE ANSWER EYEUSKSBAW
Weathering steel or another name for it is cortensteel.
Answer:
Mass = 182.4 g
Explanation:
Given data:
Number of moles of Al₂O₃ = 3.80 mol
Mass of oxygen required = ?
Solution:
Chemical equation:
4Al + 3O₂ → 2Al₂O₃
Now we will compare the moles of aluminum oxide and oxygen.
Al₂O₃ : O₂
2 : 3
3.80 : 3/2×3.80 = 5.7
Mass of oxygen:
Mass = number of moles × molar mass
Mass = 5.7 mol × 32 g/mol
Mass = 182.4 g
Answer:
3 hydrogen bonds.
Explanation:
This is because the urea molecule has an oxygen atom bound with double bonds to the central carbon atom, and this oxygen can form a hydrogen bond with water, as well as both terminal amine groups that can also form a hydrogen bond each because of the lone pair of electrons on the nitrogen group.
Answer:

Explanation:
Hello!
In this case, considering that the mass of hydrazine is missing, we can assume it is 130.0 g (a problem found on ethernet). In such a way, since we need a mass-mole-atoms relationship by which we can compute moles of hydrazine given its molar mass (32.06 g/mol), then the moles of hydrogen considering one mole of hydrazine has four moles of hydrogen and one mole of hydrogen has 6.022x10²³ atoms (Avogadro's number); therefore, we proceed as shown below:

Notice 130.0 g has four significant figures, therefore the result is displayed with four as well.
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