Answer:
29.4855 grams of chlorophyll
Explanation:
From Raoult's law
Mole fraction of solvent = vapor pressure of solution ÷ vapor pressure of solvent = 457.45 mmHg ÷ 463.57 mmHg = 0.987
Mass of solvent (diethyl ether) = 187.4 g
MW of diethyl ether (C2H5OC2H5) = 74 g/mol
Number of moles of solvent = mass/MW = 187.4/74 = 2.532 mol
Let the moles of solute (chlorophyll) be y
Total moles of solution = moles of solute + moles of solvent = (y + 2.532) mol
Mole fraction of solvent = moles of solvent/total moles of solution
0.987 = 2.532/(y + 2.532)
y + 2.532 = 2.532/0.987
y + 2.532 = 2.565
y = 2.565 - 2.532 = 0.033
Moles of solute (chlorophyll) = 0.033 mol
Mass of chlorophyll = moles of chlorophyll × MW = 0.033 × 893.5 = 29.4855 grams
Many of the boating fatalities take place after capsize, but a modest list of things to do before and after a capsize can minimize boat accidents and boat accident injuries.
Initially there is an significant list of thing to do before you even step on the boat:
1. Take the boat safety and water safely courses
2. Make certain that yourself and everyone else on the boat is wearing a well-fitting and safe life jacket.
3. Go over the place of the safety items with everyone on the boat as well as the location of the horn of the boat and the flare of the boat.
4. Paint bright color the hull of the boat in order to be seen easily from the air.
After a capsize, there are significant steps to make
1. Stay calm
2. Execute a head count and check everybody for injuries or immediate dangers.
3. Ensure that everyone has floatation device that coolers and other items that can be used.
4. Stay in the capsized boat unless dangerous.
5. Try to right the boat if someone has a knowledge on how to do so.
6. Use signal devices such as flares, bright colored life jacket, whistles, flashlights and mirror.
7. Try to reboard or climb onto it in order to get as much of your body out of the cold water as possible because treading water will ground to lose body heat sooner.
8. Do not waste energy and only signal when needed. Try to keep warm and stay strong<span />
Answer:
The climate of the earth throughout history has always been <em><u>fluctuated between hot and cold periods. </u></em>
The constant velocity that the spacecraft must travel is : 3.49 * 10⁸ m/s
<u>Given data :</u>
Distance of star from earth = 4.3 light years
Observers time = 3.7 years
<h3>Determine the constant velocity the spacecraft must travel </h3>
Observers time = 3.7 * 365 * 24 * 60 * 60
Distance of star from earth = 4.3 * 9.46 * 10¹⁵
The velocity the spacecraft must travel will be calculated using the equation
V = distance / time
= ( 4.3 * 9.46 * 10¹⁵ ) / ( 3.7 * 365 * 24 * 60 * 60 )
= 3.49 * 10⁸ m/s
Hence we can conclude that The constant velocity that the spacecraft must travel is : 3.49 * 10⁸ m/s
Learn more about space travelling : brainly.com/question/1344685
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<em>Attached below is the missing detail related to the question </em>
Answer:
4th answer
Explanation:
The gradient of a distance-time graph gives the speed.
gradient = distance / time = speed
Here, the gradient is a constant till 30s. So it has travelled at a constant speed. It means it had not accelarated till 30s. and has stopped moving at 30s.
