The expected speed is v = 85.5 km/h
v = 85.5 km/h = (85.5 km/h)*(0.2778 (m/s)/(km/h)) = 23.75 m/s
If there is an uncertainty of 2 meters in measuring the position, then within a 1-second time interval:
The lower measurement for the speed is v₁ = 21.75 m/s,
The upper measurement for the speed is v₂ = 25.75 m/s.
The range of variation is
Δv = v₂ - v₁ = 4 m/s
The uncertainty in measuring the speed is
Δv/v = 4/23.75 = 0.1684 = 16.84%
Answer: 16.8%
Answer:
The answer is aluminum foil.
The moles of HCl to neutralize the sodium hydroxide produced is<u> 0.0135 mole. </u>
Neutralization or neutralization is a chemical response wherein an acid and a base react quantitatively with each other. In a reaction in water, neutralization outcomes in there being no excess of hydrogen or hydroxide ions gift in the answer.
<u>calculation:-</u>
<u />
2Na + 2H₂O -----> 2NaOH + H₂
2 mol or 46g of Na produces 80 grams of NaOH
∴ 0.31 g of Na will produce = 80/46 × 0.31
= 0.54 gram of NaOH.
mol of NaOH = 0.54/40
= 0.0135
Since both Hcl and NaOH have the same valance factor,
1 mole NaOH is needed to neutralize 1 mol HCl
∴ 0.0135 mole of NaOH will need = 0.0135 mole of HCl
mass = 0.0135 × 36.5
=<u> 0.493 grams of HCL.</u>
Learn more about neutralizing here:-brainly.com/question/23008798
#SPJ4
Answer:
Land that gains weight can rise slowly.
Explanation:
:D
Answer:
10.78 → 4 significant figures, pH = 10.78 → [H⁺] = 1.66ₓ10⁻¹¹ M
6.78 → 3 significant figures, pH = 6.78 → [H⁺] = 1.66ₓ10⁻⁷ M
0.78 → 2 significant figures, pH = 0.78 → [H⁺] = 0.166 M
pH always can be expressed by at least 4 significant figures. The [H⁺], can be expressed by, at least 3 significant figures
Explanation:
Significant figures are the numbers of a measurement that have certainty plus a doubtful number (it is associated with the uncertainty in the measurement). For example, if we measure a paper with a ruler and the ruler measures up to centimeters we can say that the paper is 7.5 cm long, with which we know that the paper is 7 cm + 0.5 cm which we associate with uncertainty. In this case we talk about two significant figures. If the sheet measured 7.57 cm we would already be talking about a more precise measurement and in this case with 3 significant figures.
10.78 → 4 significant figures
6.78 → 3 significant figures
0.78 → 2 significant figures
To determine [H⁺], we apply 10^-pH
10⁻¹⁰°⁷⁸ = 1.66ₓ10⁻¹¹ M
10⁻⁶°⁷⁸ = 1.66ₓ10⁻⁷ M
10⁻⁰°⁷⁸ = 0.166 M
