Answer:
Explanation:
We are asked to find the specific heat capacity of a sample of lead. The formula for calculating the specific heat capacity is:
The heat absorbed (Q) is 237 Joules. The mass of the lead sample (m) is 22.7 grams. The change in temperature (ΔT) is the difference between the final temperature and the initial temperature. The temperature increases <em>from</em> 29.8 °C <em>to </em>95.6 °C.
- ΔT = final temperature -inital temperature
- ΔT= 95.6 °C - 29.8 °C = 65.8 °C
Now we know all three variables and can substitute them into the formula.
- Q= 237 J
- m= 22.7 g
- ΔT = 65.8 °C
Solve the denominator.
- 22.7 g * 65.8 °C = 1493.66 g °C
Divide.
The original values of heat, temperature, and mass all have 3 significant figures, so our answer must have the same. For the number we found that is the thousandth place. The 6 in the ten-thousandth place tells us to round the 8 up to a 9.
The specific heat capacity of lead is approximately <u>0.159 Joules per gram degree Celsius.</u>
A Lewis structure is a visual representation of the bonds between atoms and it shows the lone pairs of electrons in molecules. This structure is also referred as Lewis dot diagram. Resonance structure are multiple Lewis structure that describe a single molecule.<span>
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Answer: (3) 15
Explanation: We criss-cross down the oxidation numbers to get the subscripts for the correct formulas. That means the X has an oxidation number of 5. The element with the + oxidation number is always written first so it is +5. Of the groups names, only group 15 has +5 as an oxidation number.
<span>The mass (in grams) of 8.45 x 10^23 molecules of dextrose is 252.798g
Working:
Mw. dextrose is 180.16 g/mol
therefore 180.16 grams dextrose = 1 mole
therefore 180.16 grams dextrose= 6.022x10^23 molecules (Avogadro's number)
We have 8.45 x 10^23 molecules of dextrose.
Therefore, (180.16 divided by 6.022x10^23) times 8.45x10^23
gives the mass (in grams) of 8.45 x 10^23 molecules of dextrose;
252.798.</span>
