Answer:
Early-warning systems are essential in the case of hurricanes, severe thunderstorms, tornadoes, tsunamis, and volcanoes. All of these can wreak havoc! Let’s take a look at how meteorologists forecast these events and how early-warning systems can help us protect ourselves if we are in their paths.
Explanation:
Answer:
Four
Step-by-step explanation:
The <em>superscripts</em> in an electron configuration tell us how many electrons are in a subshell.
If the electron configuration is 1s¹ 2s¹2p², the total number of electrons is
1 + 1 + 2 = 4
The atom contains four electrons.
<em>Note</em>: this atom is in an <em>excited state</em>, because the 1s and 2s subshells can each hold one more electron.
White gold is made out of yellow gold mixed with other metals, which are added to make the alloy harder and whiter.
Even when mixed with whiter metals, white gold still retains a yellowish hue.
The quality characteristic most often used to evaluate white gold is its karat.
Answer: The missing coefficient is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
As in the products, there are 2 atoms of sodium, thus there will be 2 atoms of of sodium in the reactant as well. This will balance the number of hydrogen and oxygen atoms as well.
Thus the missing coefficient is 2.
