A student dissolves 14.8 g of ammonium nitrate (NH4NO2) in 300. g of water in a well-insulated open cup. He then observes the temperature of the water fall from 20.0°C to 15.0°C over the course of 4.3 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction: NH4NO3(s) → NH4+(aq) + NO3^- (aq)

Required:
a. Is this reaction exothermic, endothermic, or neither?
b. If you said the reaction was exothermic or endothermic, calculate the amount of heat that was released or absorbed by the reaction in this case.

a. Endothermic

b. 6586J are absorbed.

Explanation:

a. When the reaction occurs, the temperature is decreasing from 20.0°C to 15.0°C, that means the reaction is absorbing heat and is endothermic.

b. To find the heat absorbed we must use:

Q = -m*ΔT*C

Where Q is change in heat,

m is the mass of solution (300g + 14.8g = 314.8g)

ΔT is change in temperature (15.0°C - 20.0° = -5.0°C)

And C is specific heat of the solution (4.184J/g°C assuming is the same heat than the heat of pure water).

Replacing:

Q = -314.8g*-5.0°C*4.184J/g°C

Q =

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied