6.
7. 6 × 7 = 42
42 ÷ 10 = 4,2 Pizzas
You need to buy 4 or 5 Pizzas.
<h2>
Question
</h2>
A sample of methane collected when the temp was 30 C and 760mmHg measures 398 mL. What would be the volume of the sample at -5 C and 616 mmHg pressure
<h2>
Answer:</h2>
434.32mL
<h2>
Explanation:</h2>
Using the combined gas law:
= k
Where;
P = Pressure
V = Volume
T = Temperature
k = constant.
It can be deduced that:
=
= k ---------------------(i)
Where:
P₁ and P₂ are the initial and final pressures of the given gas
V₁ and V₂ are the initial and final volumes of the given gas
T₁ and T₂ are the initial and final temperatures of the gas.
<em>From the question:</em>
the gas is methane
P₁ = 760mmHg
P₂ = 616mmHg
V₁ = 398mL
V₂ = ?
T₁ = 30°C = (30 +273)K = 303K
T₂ = -5°C = (-5 +273)K = 268K
Substitute these values into equation (i) as follows;
= 
Solve for V₂
V₂ = 
V₂ = 434.32mL
Therefore, the volume of the sample at -5C and 616mmHg pressure is 434.32mL
There are several differences between<span> a </span>physical and chemical change<span> in matter or substances. A </span>physical change<span> in a substance doesn't </span>change<span> what the substance is. In a </span>chemical change<span> where there is a </span>chemical<span> reaction, a new substance is formed and energy is either given off or absorbed.</span>
Answer:
B or C
Explanation:
I don't really know sorry.