Solving for volume, what units do you use?

The energy level where an electron is located, is shown by the ______ on the periodic table

Norma-Jean [14]

Answer:

the first energy level is closest to nuclear the second energy level is a little farther away than the first

8 0

2 years ago

The idea that the earth is divided into a number of small plates that float on the mantle and slide,collide,and slip past each o

IgorLugansk [536]

Answer:

Theories

Explanation:

It is theories because it was a generalistee abstract or thinking generalising the principle of fact about Earth tectonic plates ,it was formulated and concluded as plate tectonic theories after many findings. The theories conclude that the Earth has an outer layer called lithosphere and lies overly a plastic layer called asthenosphere. The lithosphere is divided into several plates and they move close to each other where they diverge, converge or slip over one another.

7 0

2 years ago

Archeologists can determine the age of artifacts made of wood or bone by measuring the amount of the radioactive isotope 14C pre

Ahat [919]

Answer: The age of the tool is 15539 years

Explanation:

Expression for rate law for first order kinetics is given by:

$t=\frac{2.303}{k}\log\frac{a}{a-x}$

where,

k = rate constant

t = age of sample

a = let initial amount of the reactant = 100

a - x = amount left after decay process = $\frac{15.5}{100}\times 100=15.5$

a) for completion of half life:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

$t_{\frac{1}{2}}=\frac{0.693}{k}$

$k=\frac{0.693}{5730yr}=0.00012yr^{-1}$

b) for 15.5 % of original amount

$t=\frac{2.303}{0.00012}\log\frac{100}{15.5}$

$t=15539years$

Thus age of the tool is 15539 years

8 0

2 years ago

When 150. g zinc sulfide are burned in excess oxygen, 68.5 g of zinc oxide are actually produced, along with sulfur dioxide. Det

Bumek [7]

%yield = 54.6%

<h3>Further explanation</h3>

Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated

(theoretical)

General formula:

Percent yield = (Actual yield / theoretical yield )x 100%

<h3 />

Reaction

2ZnS+3O₂ ⇒ 2ZnO+2SO₂

MW ZnS = 97.474 g/mol

mol ZnS

$\tt \dfrac{150}{97.474}=1.54$

MW ZnO = 81.38 g/mol

mol ZnO (from mol ZnS as limiting reactant, O₂ excess)

$\tt \dfrac{2}{2}\times 1.54=1.54$

Actual ZnO produced

$\tt 1.54\times 81.38=125.33~g$

Theoretical production = 125.388

%yield

$\tt \dfrac{68.5}{125.33}\times 100\%=\boxed{\bold{54.6\%}}$

4 0

2 years ago

How can trace fossils provide info on how the organism lived

iragen [17]

Fossils provide a window in Earth's history by showing us how they existed in the past. They can be dated through several ways and can show us how animals and plants have evolved over millions of years. Also, fossils can help us better understand ancient disasters by the inclusion of elements (such as <span>volcanic ash or dust from major space object impacts) and how they affected the life on earth)</span>

5 0

2 years ago