Answer:
1. A
2. B and C
Explanation:
got it right in edg (see pic)
D) moles solute/liter of solution
mass of carbonic acid = 300g
molar mass of H2CO3 = 2H + C + 3 O
= 2 x 1.008+ 12.01 + 3 x 16
= 62.03g/mol
moles of H2CO3 = mass/Molar mass
= 300/62.03
= 4.8364 moles
1 mole H2CO3 has 3 moles Oxygen
4.8364 moles H2CO3 contains
= 3 x 4.8364 moles Oxygen = 14.509 moles Oxygen
moles = mass/Molar mass
mass of oxygen = moles x Molar mass of Oxygen
= 14.509 x 16
= 232.15g Oxygen
mass of oxygen in 300g of carbonic acid(H2CO3) = 232.15g
Answer: number of atoms is 5.21 · 10^24
Explanation: Atomic mass of Be is 9.012 g/mol.
Number of moles n = m/M = 78.0 g / 9.012 g/mol =
Multiply this with Avogadro number Na = 6.022*10^23 1/mol
C ( Porcupines use there’s sharp quills to defend themselves from larger predators!)
