Polar covalent, it is what happens when there is unequal bond between two atoms, where one has a slightly negative charge and one has a slightly positive charge.
Kinetic. Transform to chemical energy in muscles
<span>An atom has 16 protons and 17 neutrons. What is the chemical symbol for the atom? Consult the periodic table.
Question 8 options:
A.33Cl This would be correct.
B.32S
C.33S
D.32Cl
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Answer:
Explanation:
We know we will need an equation with masses and molar masses, so let’s gather all the information in one place.
M_r: 58.12 44.01
2C₄H₁₀ + 13O₂ ⟶ 8CO₂ + 10H₂O
m/g: 9.511
1. Moles of C₄H₁₀
2. Moles of CO₂
The molar ratio is 8 mol CO₂:2 mol C₄H₁₀
3. Mass of CO₂
<span>6.50x10^3 calories.
Now we have 4 pieces of data and want a single result. The data is:
Mass: 100.0 g
Starting temperature: 25.0°C
Ending temperature: 31.5°C
Specific heat: 1.00 cal/(g*°C)
And we want a result with the unit "cal". Now you need to figure out what set of math operations will give you the desired result. Turns out this is quite simple. First, you need to remember that you can only add or subtract things that have the same units. You may multiply or divide data items with different units and the units can combine or cancel each other. So let's solve this:
Let's start with specific heat with the unit "cal/(g*°C)". The cal is what we want, but we'ld like to get rid of the "/(g*°C)" part. So let's multiply by the mass:
1.00 cal/(g*°C) * 100.0 g = 100.0 cal/°C
We now have a simpler unit of "cal/°C", so we're getting closer. Just need to cancel out the "/°C" part, which we can do with a multiplication. But we have 2 pieces of data using "°C". We can't multiply both of them, that would give us "cal*°C" which we don't want. But we need to use both pieces. And since we're interested in the temperature change, let's subtract them. So
31.5°C - 25.0°C = 6.5°C
So we have a 6.5°C change in temperature. Now let's multiply:
6.5°C * 100.0 cal/°C = 6500.0 cal
Since we only have 3 significant digits in our least precise piece of data, we need to round the result to 3 significant figures. 6500 only has 2 significant digits, and 6500. has 4. But we can use scientific notation to express the result as 6.50x10^3 which has the desired 3 digits of significance. So the result is 6.50x10^3 calories.
Just remember to pay attention to the units in the data you have. They will pretty much tell you exactly what to add, subtract, multiply, or divide.</span>
