Answer: Work is 1.7 kJ, Power is 280 W
Explanation: Work W = mgh, power P= W/t
W = 85 kg·9.81m/s²·2 m = 1667.7 J
P = 1667.7 J / 6 s = 277.95 W
At STP, P = 1 atm, and T = 0 C
Thus, PV = nRT => V = nR(273). We will use this later...
if you have 35.4 Ca, and the molar mass of Ca is 40.08, you get .883 moles Ca. Thus, since it takes 2 moles of Ca to form a reaction, you only need half the moles of Ca of O2. Thus, n(O2) = .883/2
Tie this back to the first equation and you get
V = .442 * <span>0.082057(which is R) * 273 = 9.9 L</span>
Answer: UV Rays can't travel through glass, making it impossible to get a suntan because your body won't be able to respond if there is no UV getting to it.
Explanation: Glass absorbs and deflects a lot of UV light because the wavelengths aren't small enough to pass through and as a result, your body can't undergo its natural response of producing melanin, because the proteins activated by the UV damage won't be enacted.
<u><em>Activation Energy</em></u>
The types of energy that are involved in a chemical reaction are : (A) Activation Energy and (B) Chemical Energy. - The energy required for a chemical reaction to take place is known as the activation energy. - If the energy is less than the activation energy, the reaction will not take place.