Answer:
B. begin with a hypothesis
Explanation:
Answer:
Antibacterial specifically refers to an inhibition of growth of bacteria, whereas antibiotics refer to a general inhibition of growth of microorganisms, which could include bacteria and viruses.
Formula units in 450 g of
is 1.93 × 10²⁴ formula units.
<u>Explanation:</u>
First we have to find the number of moles in the given mass by dividing the mass by its molar mass as,

Now, we have to multiply the number of moles of Na₂SO₄ by the Avogadro's number, 6.022 × 10²³ formula units/mol, so we will get the number of formula units present in the given mass of the compound.
3.2 mol × 6.022 × 10²³ = 1.93 × 10²⁴ formula units.
So, 1.93 × 10²⁴ formula units is present in 450g of Na₂SO₄.
Answer:
The heat released by the combustion is 20,47 kJ
Explanation:
Bomb calorimeter is an instrument used to measure the heat of a reaction. The formula is:
Q = C×m×ΔT + Cc×ΔT
Where:
Q is the heat released
C is specific heat of water (4,186kJ/kg°C)
m is mass of water (1,00kg)
ΔT is temperature change (23,65°C - 20,45°C)
And Cc is heat capacity of the calorimeter (2,21kJ/°C)
Replacing these values the heat released by the combustion is:
<em>Q = 20,47 kJ</em>