Answer:
Required number of moles of ideal gas is 0.877 moles.
Explanation:
Pressure (P) = 0.850 atm
Temperature (T) = 295 K
Volume (V) = 25 ltr
Universal gas constant (R) = 0.0821
no of moles (n) = ?
we have the ideal gas equation as:
PV= nRT
or, 0.850× 25 = n × 0.0821 × 295
or, n = 0.877 moles
Hence the required number of moles of an ideal gas is 0.877 moles.
Answer : The balanced chemical reaction will be,

Explanation :
Balanced chemical reaction : It is defined as the reaction in which the number of atoms of individual elements present on reactant side must be equal to the product side.
If the amount of atoms of each type on the left and right sides of a reaction differs then to balance the equation by adding coefficient in the front of the elements or molecule or compound in the chemical equation.
The coefficient tell us about that how many molecules or atoms present in the chemical equation.
The given chemical reaction is,

This reaction is an unbalanced chemical reaction because in this reaction number of hydrogen bromine atoms are not balanced.
In order to balance the chemical equation, the coefficient '2' put before the
and we get the balanced chemical equation.
The balanced chemical reaction will be,

Ultraviolet Rays ( UV rays) can harm humans because they can cause sunburn, and skin cance if you stay out in the sun for too long.
Two steps by inspection 1 qt = 0.25 gallons, 13.6 g/mL = 13.6 kg/L
0.25 gallon x 3.785411784 L/gallon x 13.6 kg/L x 1 lb/0.45359237 kg = 28.374 lb.
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