Explanation:
The mode is the most common number.
Um = 55
The mean is the sum of the numbers divided by the quantity.
Uavg = (38 + 44 + 45 + 48 + 50 + 55 + 55 + 57 + 58 + 60) / 10
Uavg = 51
The RMS (root mean square) is the square root of the sum of the squares of the numbers divided by the quantity.
Urms = √[(38² + 44² + 45² + 48² + 50² + 55² + 55² + 57² + 58² + 60²) / 10]
Urms = 51.451
Answer:
- Molar mass = 608.36 g/mol
Explanation:
It seems the question is incomplete. However a web search us shows this data:
" Reserpine is a natural product isolated from the roots of the shrub Rauwolfia serpentina. It was first synthesized in 1956 by Nobel Prize winner R. B. Woodward. It is used as a tranquilizer and sedative. When 1.00 g reserpine is dissolved in 25.0 g camphor, the freezing-point depression is 2.63 °C (Kf for camphor is 40 °C·kg/mol). Calculate the molality of the solution and the molar mass of reserpine. "
The <em>freezing-point depression</em> is expressed by:
We put the data given by the problem and <u>solve for m</u>:
- 2.63 °C = 40°C·kg/mol * m
For the calculation of the molar mass:<em> Molality</em> is defined as moles of solute per kilogram of solvent:
- 0.06575 m = Moles reserpine / kg camphor
- 25.0 g camphor ⇒ 25.0/1000 = 0.025 kg camphor
We<u> calculate moles of reserpine:</u>
- 0.06575 m = Moles reserpine / 0.025 kg camphor
- Moles reserpine = 1.64x10⁻³ mol
Finally we use the mass of reserpine and the moles to calculate <u>the molar mass</u>:
- 1.00 g reserpine / 1.64x10⁻³ mol = 608.36 g/mol
<em>Keep in mind that if the data in your problem is different, the results will be different. But the solving method remains the same.</em>
Answer:
2.4 ×10^24 molecules of the herbicide.
Explanation:
We must first obtain the molar mass of the compound as follows;
C3H8NO5P= [3(12) + 8(1) + 14 +5(16) +31] = [36 + 8 + 14 + 80 + 31]= 169 gmol-1
We know that one mole of a compound contains the Avogadro's number of molecules.
Hence;
169 g of the herbicide contains 6.02×10^23 molecules
Therefore 669.1 g of the herbicide contains 669.1 × 6.02×10^23/ 169 = 2.4 ×10^24 molecules of the herbicide.
<span>It takes 3 breaths to get to 1.2 l. One breath is then (1.2 l) / 3 breaths = .4l/breath.
To get to 3.0 l we need the difference from 1.2 l.
3.0-1.2 = 1.8 l.
Divide the difference by liters/breath (.4) to get how many needed breaths.
(1.8 l)/(.4 l/breath) = 4.5 breaths to get the balloon to 3.0 l.
In total there were 3 breaths+ 4.5 breaths = 7.5breaths to get to 3.0 l.
To find the total moles multiply 7.5breaths by .060 moles/breath
7.5 breaths*.060moles/breath = .45moles</span>
Answer
its a potassium elements
Explanation:
K 2,8,8,1 period num 4
group 1A
or 1s1 ,2s2 2p6, 3s1
its a metal reacted rapidly with water to form a colorless basic solution of potassium hydroxide (KOH) and hydrogen gas (H2). The reaction continues even when the solution becomes basic. The resulting solution is basic because of the dissolved hydroxide. The reaction is exothermic.
