Answer:
9000 BC
Explanation:
Although various copper tools and decorative items dating back as early as 9000 BCE have been discovered, archaeological evidence suggests that it was the early Mesopotamians who, around 5000 to 6000 years ago, were the first to fully harness the ability to extract and work with copper.
Answer:
18,1 mL of a 0,304M HCl solution.
Explanation:
The neutralization reaction of Ba(OH)₂ with HCl is:
2 HCl + Ba(OH)₂ → BaCl₂ + 2 H₂O
The moles of 17,1 mL≡0,0171L of a 0,161M Ba(OH)₂ solution are:
= 2,7531x10⁻³moles of Ba(OH)₂
By the neutralization reaction you can see that 2 moles of HCl reacts with 1 mole of Ba(OH)₂. For a complete reaction of 2,7531x10⁻³moles of Ba(OH)₂ you need:
= 5,5062x10⁻³moles of HCl.
The volume of a 0,304M HCl solution for a complete neutralization is:
= 0,0181L≡18,1mL
I hope it helps!
Answer:
4.62 M
Explanation:
Molarity = moles/volumes (L), so you need to find the moles and the volumes in liters.
Finding the volume is easy because you just have to convert mL to L, so the volume is 0.45 L
Next, find the moles. You can do this by using the molar mass of aluminum to convert the grams to moles. The molar mass of aluminum is 26.98 g/mol.
56 g * (1 mol/26.98 g) = 2.08 mol
Now, divide the moles (2.08) by the volume (.45 L)
Molarity = 4.62 M
Can you be more specific?
...Diamond is the best conductor of heat, but heat also transmits readily through many other substances. Do you have multiple choice?
