Answer:
Strontium
Explanation:
In the periodic table, an element with two (2) valence electrons is found on group 2. Group 2 is a group of the periodic table that harbors element called ALKALINE EARTH METALS. As the name implies, they are metals that possess shiny and solid characteristics at room temperature.
Group 2 elements include the following: Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), barium (Ba), and radium (Ra). Based on the descriptive information in this question, the element being described is a GROUP 2 element. Based on the elements in the option, only STRONTIUM (Sr) is a group 2 element.
The nuclear reaction occurring is known as alpha-decay, and during this process, an alpha particle is released from a heavy radioactive nucleus to form a lighter more stable nucleus. The alpha particle is equivalent to a helium nucleus, which means it contains 2 protons and two neutrons (net charge of +2)
The decay equation is:
Rn → Po + α
Answer:
Electrical energy = 130000000 J and Heat energy = 520000000 J
Explanation:
Multiply the amount of joules from the last question (650000000) by .20 and .80. (Which are the percentages)
Answer: oil spill, forest fire
Explanation:
The short term environmental change is a change that occur in an environment which exerts it's effect over the environment and the living beings for a short duration. The damage caused by the short term environmental change can be recovered in a short time. The oil spill and forests fire are the example of short term environmental changes.
The oil spill will reduce the abundance of the aquatic species until the oil is circulated out at the bay of the water body therefore, it is a short term environmental change.
Forests fire will remain ignited for a short period but can be destructive enough to cause damage to flora and fauna species. As time passes the reduced populations of flora and fauna can be recovered again.
