Answer:
Sr is the more metallic element
Bi is the more metallic element
O is the more metallic element
As is the more metallic element
Explanation:
One thing should be clear; metallic character increases down the group but decreases across the period.
Hence, as we move across the period, elements become less metallic. As we move down the group elements become more metallic.
This is the basis upon which decisions were made about the metallic character of each of the elements listed above.
Answer:
We need 4.28 grams of sodium formate
Explanation:
<u>Step 1:</u> Data given
MW of sodium formate = 68.01 g/mol
Volume of 0.42 mol/L formic acid = 150 mL = 0.150 L
pH = 3.74
Ka = 0.00018
<u>Step 2:</u> Calculate [base)
3.74 = -log(0.00018) + log [base]/[acid]
0 = log [base]/[acid]
0 = log [base] / 0.42
10^0 = 1 = [base]/0.42 M
[base] = 0.42 M
<u>Step 3:</u> Calculate moles of sodium formate:
Moles sodium formate = molarity * volume
Moles of sodium formate = 0.42 M * 0.150 L = 0.063 moles
<u>Step 4:</u> Calculate mass of sodium formate:
Mass sodium formate = moles sodium formate * Molar mass sodium formate
Mass sodium formate = 0.063 mol * 68.01 g/mol
Mass sodium formate = 4.28 grams
We need 4.28 grams of sodium formate
<span> purity of the substance is usually the main error (for example: water with impurities will have m.p. less than 273K or 0 degree celcius while it's b.p. will be greater than 373K or 100 degree celcius). </span>
<span>-> air/ room temperature (it takes longer to cook in mountains and shorter at beaches) </span>
<span>-> parallax error (error by determining the meniscus of the thermometer) </span>
<span>and many more..</span>
Answer:
C) condensation of steam inside.
Explanation:
Steam only condenses on a surface when the temperature of that surface is less than the saturation temperature for the pressure at which the steam is found. During this process the water molecule releases energy in the form of heat, in this case the water contained in the can brings a very high temperature causing the temperature of the cold water bath to rise abruptly thus releasing energy which makes the can crushed.