Answer:
2.12atm
Explanation:
Boyle's Law: P1V1 = P2V2
Manipulate to solve for unknown: P2 = P1V1/V2
Substitute values: P2=(1.2atm)(4.6L)/2.6L
P2 = 2.1230769atm
Round to 3 sig figs to get 2.12atm
Explanation:
no.A (He) I think.............
The answer is 40.
We can solve this by finding out the number of protons, and neutrons. Atomic number of an element means the number of protons in that element. So, the atom has 30 protons if the atomic number is 30.
On the other hand, mass number is the total number of protons and neutrons, but not electrons, because they're too light comparing to the other 2. Therefore, we can simply solve the number of neutrons in the atom by subtracting the number of protons from the mass number. 70 - 30 = 40.
Therfore, the number of neutrons is 40.
Mole is equal to mass of the element divided by molar mass of the element. that is
mole=mass/molar mass
From periodic table calcium has a molar mass of 40 g/mol
moles is therefore =800g/40g/mol=20moles
I think it’s either 1 or 2 !!