Depends on where you live but generally speaking it is either June or July
Let's define an ionic and covalent bond.
An ionic bond occurs between a metal and non-metal. These electrons are transferred between atoms. A Covalent bond occurs between a nonmetal and a nonmetal. These electrons are shared between atoms.
First, identify whether each element is metal or nonmetal. If you need a little help, refer to an online periodic table for guidance.
We see that both Hydrogen and Sulfur are nonmetals. That eliminates both choice 1 and 3.
Then, understanding that within covalent bonds, electrons are shared, choice 4 is eliminated.
Thus, the answer is 2.
In physics, power is the rate of doing work. It is the amount of energy consumed per unit time. Having no direction, it is a scalar quantity. In the SI system, the unit of power is the joule per second (J/s), known as the watt in honour of James Watt, the eighteenth-century developer of the steam engine.
If i am not mistaken ,
density = mass / volume
density = 7.87 g/cm3
volume = 2.5 cm3
thus ,
mass = density x volume
7.87 g/cm3 x 2.5 cm3 = 19.675 g
Building a space station in orbit is a safety measure. If a rocket fails to bring up the entire space station in one piece it would be extremely expensive to build a new one. Bringing it up in multiple places ensures less money would be lost if the rocket fails.
