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Answer:
Exothermic reaction
Explanation:
Since in an exothermic reaction heat is released, the products will be more stable than the reactants.
Answer: The pressure in atmospheres is 0.674 in the container if the temperature remains constant.
Explanation:
Boyle's Law: This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.
(At constant temperature and number of moles)
where,
= initial pressure of gas = 205 kPa
= final pressure of gas = ?
= initial volume of gas = 4.0 L
= final volume of gas = 12000 ml = 12 L (1L=1000ml)
(1kPa=0.0098atm)
Therefore, the pressure in atmospheres is 0.674 in the container if the temperature remains constant.
The chalk particles embed themselves into the small pores on the surface.
Although a chalkboard seems smooth to the touch, it is quite rough at the microscopic level, with <em>pores</em> that reach below the surface.
When you drag chalk across the board, friction causes small particles of chalk to rub off onto the surface.
If you leave the markings for a long time, some of the chalk particles will work their way into the pores.
A brush will remove the surface particles, but <em>it will not be able to get at the particles in the pores</em>.