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2 years ago

Please help! USATestprep K12

Chemistry

2 answers:

NeX [460]2 years ago

8 0

Answer:

its none above

Explanation:

food webs have arrows that show the flow of energy from one orhganism to the next

bar graphs have bars and numbers and diagrams have words and pictures so it D

ycow [4]2 years ago

6 0

Answer: C

Explanation:

You might be interested in

At 25∘C, the decomposition of dinitrogen pentoxide, N2O5(g), into NO2(g) and O2(g) follows first-order kinetics with k=3.4×10−5

Annette [7]

Answer:

4600s

Explanation:

$2N_{2}O_{5}(g) - - -> 4NO_{2}(g) +O_{2}$

For a first order reaction the rate of reaction just depends on the concentration of one specie [B] and it’s expressed as:

$-\frac{d[B]}{dt}=k[B] - - - -\frac{d[B]}{[B]}=k*dt$

If we have an ideal gas in an isothermal (T=constant) and isocoric (v=constant) process.

PV=nRT we can say that P = n so we can express the reaction order as a function of the Partial pressure of one component.

$-\frac{d[P(B)]}{P(B)}=k*dt$

$-\frac{d[P(N_{2}O_{5})]}{P(N_{2}O_{5})}=k*dt$

Integrating we get:

$\int\limits^p \,-\frac{d[P(N_{2}O_{5})]}{P(N_{2}O_{5})}=\int\limits^ t k*dt$

$-(ln[P(N_{2}O_{5})]-ln[P(N_{2}O_{5})_{o})])=k(t_{2}-t_{1})$

Clearing for t2:

$\frac{-(ln[P(N_{2}O_{5})]-ln[P(N_{2}O_{5})_{o})])}{k}+t_{1}=t_{2}$

$ln[P(N_{2}O_{5})]=ln(650)=6.4769$

$ln[P(N_{2}O_{5})_{o}]=ln(760)=6.6333$

$t_{2}=\frac{-(6.4769-6.6333)}{3.4*10^{-5}}+0= 4598.414s$

4 0

3 years ago

usando el concepto de valencia para los elementos S, P Y Br predice las formulas de los compuestos mas simples formados por esto

hram777 [196]

Explanation:

Teniendo en cuenta los numeros de oxidacion negativos de cada uno

P:fosforo(-3)

S:Azufre (-2)

Br:Bromo (-1)

Y el H: hidrogeno con una valencia

positiva de +1

los compuesto que se formaran son los siguientes

1 H3P= fosfuro de hidrogeno

2 H2S= sulfuro de hidrogeno

3 HBr= Acido bromhidrico

ESPERO ABERTE AYUDADO ;D

6 0

2 years ago

Atoms of a substance are rearranged _______.

Yanka [14]

Atoms are never rearranged

6 0

3 years ago

Granite was formed slowly as magma cooled. What is the result of the slow cooling?

Aleksandr-060686 [28]

Igneous rocks from cooling magma. Granite is an igneous rock formed from magmathat cooled slowly underground. As the magma slowly cools, large mineral crystals form.

4 0

3 years ago

Read 2 more answers

Mature elephants consume an average of 600 pounds of food per day. If an elephant

MAXImum [283]

Answer:

$\large \boxed{\text{4 600 000 kg or 4600 Mg}}$

Explanation:

1. Calculate the adult life

If the elephant is an adult from its 10th birthday until the day before its 56th birthday, its

Adult life = 55 - 10 + 1 = 46 yr

2. Convert years to days

$\text{Adult life} = \text{46 yr} \times \dfrac{\text{365.25 da}}{\text{1 yr}} = \text{16 800 da}$

3. Convert days to pounds of feed

$\text{Feed} = \text{16 800 da} \times \dfrac{\text{600 lb}}{\text{1 da}} = 1.01 \times 10^{7} \text{ lb}$

4. Convert pounds to kilograms and megagrams

$\text{Feed} =1.01 \times 10^{7} \text{ lb} \times \dfrac{\text{1 kg}}{\text{2.20 lb}} =\textbf{4 600 000 kg} = \textbf{4600 Mg}\\\\\text{The elephant will eat $\large \boxed{\textbf{4 600 000 kg or 4600 Mg}}$ of food.}$

Note: The answer can have only two significant figures because that is all you gave for age of the elephant.

5 0

3 years ago