How much heat is required to warm 1.50 L of water from 25.0 oC to 100.0 oC? (Assume a density of 1.0 g/mL for water.) If the
If the heat needed is supplied by combustion of pentane as shown below:
C5H12(l)+8 O2(g)→5 CO2(g)+6 H2O(g) ΔH=−3244.8 kJ
How many grams of pentane is needed?
In: Chemistry
0.737 g of a sample contains iron. all amount of iron is oxidied to Fe2+ on Pt anode which has constant potential at 1.0 V against SCE. an iodide chemical coulometer is used to measure the amont of current (Q), the amount of released iodide needs 27.mL of thiosulfate (0.0217 N). calculate the percentage of Fe3O4 in the sample. (current 10 mA)
In: Chemistry
A car being driven by a cyber school physics student is moving with a velocity of 100 km/hr. As the car comes over the hill the student notices a train crossing the highway 0.4 km in front of him. If he immediately applies the brakes which can give the car a deceleration of 1.0 m/s2, determine whether or not a collision will occur. Explain and show all calculations!
In: Physics
A pot of water is boiling under one atmosphere of pressure. Assume that heat enters the pot only through its bottom, which is copper and rests on a heating element. In two minutes, the mass of water boiled away is m = 3.5 kg. The radius of the pot bottom is R = 10.0 cm and the thickness is L = 1.0 mm. What is the temperature of the heating element in contact with the pot?
In: Physics
Suppose the average intensity of the solar radiation that
strikes normally on a surface just outside Earth's atmosphere is
1.4 kW/m2. (It is actually 1.4 kW/m2.)
(a) What would be the radiation pressure
pr exerted on this surface, assuming complete
absorption? (b) For comparison, find the ratio of
pr to Earth's sea-level atmospheric pressure,
which is 1.0 x 105 Pa.
In: Physics
There is a disk of cartilage between each pair of vertebrae in your spine. Young's modulus for cartilage is 1.0 × 106N/m2. Suppose a relaxed disk is 4.0 cm in diameter and 5.0 mm thick.
If a disk in the lower spine supports half the weight of a 76 kg person, by how many mmmm does the disk compress?
Express your answer using two significant figures.
In: Physics
1(i). Derive the solution to mass balance equations for the
nth-order reactions occuring in a CSTR and in a PFR at steady
state.
(II) A first-order reaction A--- products (the long
dash represents an arrow) is to be carried out in a CSTR. The
reaction rate constant was determined to be 1.0/h. What is the
residence time required for 90% conversion of the reactant provided
there are no changes in temperature and density of the
system?
In: Chemistry
The following cash outlays are anticipated for a I-year project. Prepare a cumulative cash flow curve. (10 points)
January - $1.1 million; February - $600,000; March - $700,000; April - $1.4 million; May - $1.7 million; June - $2.0 million; July $2.1 million; August - $1.7 million; September - $1.0 million; October - $700,000; November - $400,000; December - $200,000
In: Accounting
A 200 g mass hangs from a massless spring (k = 10 N/m). At t = 0.0 s, the mass is 20 cm below the equilibrium point and moving upward with a speed of 100 cm/s. What is the a. oscillation frequency? b. distance from equilibrium when the speed is 50 cm/s? c. distance from equilibrium at t = 1.0 s?
In: Physics
On 16 March 2020, Hong Kong Monetary Authority (HKMA) announced that “… the countercyclical capital buffer (CCyB) for Hong Kong is being reduced from 2.0% to 1.0% with immediate effect.”
a. Briefly explain the measure ‘countercyclical capital buffer’ under the Basel III Regulatory Capital Framework.
b. Why HKMA would like to reduce the ‘countercyclical capital buffer’ at this moment?
In: Finance