Answer: <em>Running water, even at a trickle, helps prevent pipes from freezing. If you decide to use fuel-burning equipment, such as a kerosene heater, ensure it is vented to outside and kept clear of any vents. Keep garage doors closed if there are water supply lines in the garage.</em>
Explanation:
Firstly, the density of any substance is represented by the mass (amount of matter) as divided by the volume(amount of space). According to external websites, the mass of a penny is 2.5 grams.However, the volume of a penny is .35cm to the power of 3 (due to the thickness of the penny being extremely minimal.Thus the amount of density is extremely little). Therefore, the density of a penny is 0.875 g/cm cubed (dimensional analysis).As for an invention that could be used, that is possible with the usage of a series of measurements that can both calculate mass and volume and directly allocate that to attain density
Answer:
6.6253*10²¹molecules of ethane (C₂H₆) are present in 0.334 g of C₂H₆
Explanation:
Avogadro's Number is the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of that substance. Its value is 6.023 * 10²³ particles per mole. Avogadro's number applies to any substance.
In this case, being:
the molar mass of ethane C₂H₆ is:
C₂H₆: 2*12 g/mole + 6* 1 g/mole= 30 g/mole
Then you can apply the following rule of three: if 30 grams of C₂H₆ are present in 1 mole, 0.334 grams of C₂H₆ in how many moles are present?
![moles of C_{2} H_{6} =\frac{0.334 grams*1 mole}{30 grams}](https://tex.z-dn.net/?f=moles%20of%20C_%7B2%7D%20H_%7B6%7D%20%3D%5Cfrac%7B0.334%20grams%2A1%20mole%7D%7B30%20grams%7D)
moles of C₂H₆=0.011
Finally, taking into account the definition of Avogadro's number, you can apply the following rule of three: if there are 6.023 * 10²³ molecules of C₂H₆ in 1 mole, how many molecules are there in 0.011 moles?
![molecules of C_{2} H_{6} =\frac{0.011 moles*6.023*10^{23}molecules }{1 mole}](https://tex.z-dn.net/?f=molecules%20of%20C_%7B2%7D%20H_%7B6%7D%20%3D%5Cfrac%7B0.011%20moles%2A6.023%2A10%5E%7B23%7Dmolecules%20%7D%7B1%20mole%7D)
molecules of C₂H₆= 6.6253*10²¹
<u><em>6.6253*10²¹molecules of ethane (C₂H₆) are present in 0.334 g of C₂H₆</em></u>
1 mile = 1609 m
and 1 hour = 3600 seconds
so we can convert 1220 m/s into miles per hour as following:
(1220 m/s) ×( 3600 sec/hour) ÷ (1609 m/mile)
= 2729.65 mile/hour
<span>1.6 g
First, calculate the change in temperature.
30.5 - 23.2 = 7.3 K
Now we have 3 pieces of data, the units involved are K, J/(g K), and J. We wish to create a result with the units being g. Let's start with the specific heat.
0.90 J/(g K)
Now let's cancel out the K by multiplying by our data with K
0.90 J/(g K) * 7.3 K = 6.57 J/g
Now we want to cancel out the J and get g on top. We can do that by dividing the J value we have by the calculated value above. So
10.3 J / 6.57 J/g = 1.567732116 g
Rounding to 2 significant figures gives us a mass of 1.6 g
Remember, for most problems, simply look at the units you have and what you desire for the units in the final result. By paying attention to this, the math operations you need are pretty automatic.</span>