The answer choices:
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[B]: rusting iron ; AND:
[D]: rubbing a marker on paper;
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are BOTH examples of a chemical reaction.
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Note: Rusting iron is, more specifically, a "redox" (or, "oxidation/reduction") reaction.
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Answer:
<em>C</em> Na+ = 0.228 M
Explanation:
M 2M M
∴ mol Na2S = (0.0478 L)*(0.801 mol/L) = 0.0383 mol
∴V sln = 336.7 mL = 0.3367 L
⇒ <em>C</em> Na2S sln = 0.0383 mol / 0.3367 L = 0.114 M
∴ mol Na+ = (0.0383 mol Na2S)*( 2 mol Na+/ mol Na2S) = 0.0766 mol
⇒ <em>C</em> Na+ = 0.0766 mol / 0.3367 L = 0.2275 M
Answer:
Solid potassium iodide decomposes into solid potassium and iodide gas.
Explanation:
The answer given has a subscript "2" on the iodine at the start of the equation. Why is the 2 there as a subscript?
Answer: 565.245kJ
To answer this question, you need to know how much water heat capacity which was 4.187 kJ/kg K. First, we need to find the calorie absorbed by water. Since the sample is 1kg, the initial temperature is 21 ∘C and final temperature is 34.5 <span>∘C then the calculation would be:
Energy= (Final temp - initial temp) * heat capacity * mass
Energy = (34.5-21) </span>∘C * 4.187 * kJ/kg K * 1kg= 56.5245 kJ
The energy is made from 0.1 gram, then for 1 gram of energy it should be:
1 gram/ 0.1gram x 56.5245 kJ= 565.245kJ
HCl = H⁺ + Cl⁻
c(HCl)=9.8*10⁻⁵ mol/l
pH=-lg[H⁺]
[H⁺]=c(HCl)
pH=-lg{c(HCl)}
pH=-lg{9.8*10⁻⁵}=4.009
pH=4.009