After two half-lives or 60 years, 7.5 g of the element will be left.
<u>Explanation:</u>
<u>Half-life:</u>
- In simple words, Half-life can be defined as the amount of time needed for a quantity to fall to half its value as contained at the beginning of the time period.
- In this problem the half-life of the element is thirty years, then after thirty years half of the sample would have decayed and half would be left as it is.
- After thirty years (The first half-life ) 30 /2 = 15 g declines and 15 g remains disappeared.
- And after another sixty years (The two half-lives) 15 /2 = 7.5 g declines and 7.5 g remains disappeared.
- After two half-lives or 60 years, 7.5 g of the element will be left.
Answer:The rock formations of eastern North America, Western Europe, and northwestern Africa were later found to have a common origin, and they overlapped in time with the presence of Gondwanaland. Together, these discoveries supported the existence of Pangea.When Rodinia broke up, it split into three pieces: the supercontinent of Proto-Laurasia, the supercontinent of Proto-Gondwana, and the smaller Congo craton. Proto-Laurasia and Proto-Gondwana were separated by the Proto-Tethys Ocean.
Don't take my full word on it, this is what i think
Explanation:
In low light no plants grow. With no plants no animals can eat so less animals remain or stay there. With less animals less animals respire and breathe out CO2.
Distillation, Filtration, evaporation, and Chromatography
The filtration process is generally used to separate a suspension mixture where small solid particles are suspended in liquid or air.
Distillation uses boiling to separate mixtures of liquid solutions. It takes into account that different substances in the mixture will have different boiling points..
Chromatography is the separation of a mixture by passing it in solution or suspension or as a vapor (as in gas chromatography) through a medium in which the components move at different rates
Evaporation is a technique used to separate out homogenous mixtures where there is one or more dissolved solids. This method drives off the liquid components from the solid components