The appropriate response is gamma radiation. Alpha particles can be halted via air. UV radiation can be halted by a typical layer of clothing.Beta particles can be ceased by the thick plastic suit. Just gamma radiation can enter the substantial suit. It must be halted by thick dividers of lead or cement.
substitute: <span><span>t<span>1/2</span></span>=<span><span>ln(2)</span>k</span>→k=<span><span>ln(2)</span><span>t<span>1/2</span></span></span></span>
Into the appropriate equation: <span>[A<span>]t</span>=[A<span>]0</span>∗<span>e<span>−kt</span></span></span>
<span>[A<span>]t</span>=[A<span>]0</span>∗<span>e<span>−<span><span>ln(2)</span><span>t<span>1/2</span></span></span>t</span></span></span>
<span>[A<span>]t</span>=(250.0 g)∗<span>e<span>−<span><span>ln(2)</span><span>3.823 days</span></span>(7.22 days)</span></span>=67.52 g</span>
First one because Common synthetic materials are nylon, acrylic, polyester, carbon fiber, rayon and spandex. Synthetic materials are made from chemicals and are usually based on polymers. They are stronger than natural and regenerated materials.
The answer would be b. Temperature of the solution increases
Temperature determines the kinetic energy of the water molecule. Higher temperature will cause the molecule to moves faster and the compound (KNO3) could break solute molecule easier make it become more soluble. A higher pressure will increase the solubility of a gas, not solid
69. The student's skin was obviously warmer than the initial temperature of the bracelet. According to the second law of thermodynamics, heat transfers from a higher temperature to a lower temperature hence heat transfers from the student's skin to the bracelet warming up the bracelet.
70. moles of copper=mass of copper/molar mass of copper
=30.1g/(63.55g/mol)= 0.4736 moles Cu
71. Delta H( heat released) = mCp(deltaT) = 30.1g(0.385 J/gK)(33-19)K = 162.23J
72. Copper is chemically less active than iron.