They were created with stone and wood and sometimes even bones, I hope this helped!
The answer is D because they would have to make quarries just below the surface to mine
Mineral ores much quicker (Quarries- a large hole/pit under ground used to get stone and minerals)
Answer:
mass HF = 150.05 g
Explanation:
- SiO2(s) + 4HF(g) → SiF4(g) + 2H2O(l)
⇒ Q = (ΔH°rxn * mHF) / (mol HF * MwHF )
∴ MwHF = 20.0063 g/mol
∴ mol HF = 4 mol
∴ ΔH°rxn = - 184 KJ
∴ Q = 345 KJ
mass HF ( mHF ):
⇒ mHF = ( Q * mol HF * MwHF ) / ΔH°rxn
⇒ mHF = ( 345 KJ * 4mol HF * 20.0063 g/mol ) / 184 KJ
⇒ mHF = 150.05 g HF
Answer: Neutron matter is equivalent to a chemical element with atomic number 0, which is to say that it is equivalent to a species of atoms having no protons in their atomic nuclei. Neutron matter decays quickly into hydrogen. Neutron matter has no electronic structure on account of its total lack of electrons.
Explanation:
