Answer:
They use hypotheses to guess a result based on what they already know. Observations are used to record the results of an experiment. Predictions are used to have an expected outcome of a test, thinking the hypothesis is correct. Experiments are used to test the hypothesis.
The pH of pure water has been best described as neutral pH with equal hydronium and hydroxide ions. Thus, option A is correct.
pH has been described as the measurement of hydrogen ions in a solution. The pH has been measured on a scale of 1-14. pH 7 has been the neutral pH.
The higher hydronium ion concentration tends to move the pH from 7 towards 1. The higher hydroxide ion concentration tends to move the pH above 7.
The neutral pH has been neither acidic nor basic with the equal constituents of hydronium and hydroxide ion in the solution.
Thus, the pH of pure water has been 7. It has neutral pH with equal hydronium and hydroxide ions. Thus, option A is correct.
For more information about the pH of the solution, refer to the link:
brainly.com/question/4975103
The answer is: mass is 40.17 kilograms.
d = 0.758 g/mL; density of fuel.
V = 14.0 gal; volume.
A gallon is a unit of volume in both the US customary and imperial systems of measurement. The US gallon is defined as 231 cubic inches (3.785 liters).
1 gal = 3785.41 mL.
V = 14 gal · 3785.41 mL:
V = 52995.74 mL.
m = 52995.74 mL · 0.758 g/mL.
m = 40170.77 g; mass of fuel.
m = 40170.77 g ÷ 1000 g/kg.
m = 40.17 kg.
Answer:
50 g of S are needed
Explanation:
To star this, we begin from the reaction:
S(s) + O₂ (g) → SO₂ (g)
If we burn 1 mol of sulfur with 1 mol of oxygen, we can produce 1 mol of sulfur dioxide. In conclussion, ratio is 1:1.
According to stoichiometry, we can determine the moles of sulfur dioxide produced.
100 g. 1mol / 64.06g = 1.56 moles
This 1.56 moles were orginated by the same amount of S, according to stoichiometry.
Let's convert the moles to mass
1.56 mol . 32.06g / mol = 50 g
Answer: 404.04 kJ.
Explanation:
To calculate the moles, we use the equation:
moles of

According to stoichiometry :
2 moles of
on burning produces = 1036 kJ
Thus 0.78 moles of
on burning produces =
Thus the enthalpy change when burning 26.7 g of hydrogen sulfide is 404.04 kJ.