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3 years ago

Guys please I need an answer for this asap

1 answer:

6 0

I need more information, there are meant to be coefficients in front of one of those ..

but you’d put .2 over the coefficients, and if there is not one, you put an X. then you will cross multiply, and divide if you have 2x or something greater than X.

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According to the ph scale, what is the approximate ph of ammonia solution?

UNO [17]

I believe that the answer is 11.5

5 0

3 years ago

Xelga [282]

Answer:

Used to make animal Feed

Explanation:

3 0

3 years ago

In the early 1960s, radioactive strontium-90 was released during atmospheric testing of nuclear weapons and got into the bones o

Advocard [28]

Answer:

52.54 %

Explanation:

Half life = 29 years

$t_{1/2}=\frac {ln\ 2}{k}$

Where, k is rate constant

So,

$k=\frac {ln\ 2}{t_{1/2}}$

$k=\frac {ln\ 2}{29.0}\ {years}^{-1}$

The rate constant, k = 0.023902 hour⁻¹

From 1964 to 1991:

Time = 27 years

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

So,

$\frac {[A_t]}{[A_0]}=e^{-0.023902\times 27}$

$\frac {[A_t]}{[A_0]}=0.5245$

The strontium-90 remains in the bone = 52.54 %

5 0

3 years ago

Sort the following elements in order from least reactive to most reactive.

SVEN [57.7K]

Sorting the chemical elements in order from least reactive to most reactive, we have:

1. Fluorine (F).

2. Arsenic (As).

3. Antimony (Sb).

4. Silicon (S).

Given the following chemical elements:

Antimony (Sb).

Silicon (S).

Fluorine (F).

Arsenic (As).

Reactivity can be defined as a chemical property which determines how readily a chemical element bonds with other chemical elements, in order to form a new chemical compound.

Generally, the ability of a chemical element to bond with other chemical elements is largely (highly) dependent on the number of valence electrons it has in the outermost shell of its atomic nucleus.

As a general rule, chemical elements that are having fewer number of valence electrons are the most reactive while those having higher valence electrons are least reactive.

Also, chemical reactivity decreases down a group on the periodic table.

Based on the periodic table, the valency for the given chemical elements are:

Antimony (Sb): 5 valence electrons.

Silicon (S): 4 valence electrons.

Fluorine (F): 7 valence electrons.

Arsenic (As): 5 valence electrons.

In conclusion, sorting the chemical elements in order from least reactive to most reactive, we have:

1. Fluorine (F).

2. Arsenic (As).

3. Antimony (Sb).

4. Silicon (S).

Find more information: brainly.com/question/18214726

4 0

2 years ago

If the cylindrical pistons are 25.000 cm in diameter at 20.0 ∘c, what should be the minimum diameter of the cylinders at that te

attashe74 [19]

Refer to the diagram shown below.

The piston supports the same load W at both temperatures.
The ideal gas law is
$pV=nRT$
where
p = pressure
V = volume
n = moles
T = temperature
R = gas constant

State 1:
T₁ = 20 C = 20+273 = 293 K
d₁ = 25 cm piston diameter

State 2:
T₂ = 150 C = 423 K
d₂ = piston diameter

Because V, n, and R remain the same between the two temperatures, therefore
$\frac{p_{1}}{T_{1}} = \frac{p_{2}}{T_{2}}$

If the supported load is W kg, then
$p_{1} = \frac{W \, N}{ \frac{\pi}{4} d_{1}^{2}} = \frac{4W \, N}{\pi (0.25 \, m)^{2}} = 20.3718W \, Pa$
Similarly,
$p_{2} = \frac{4W}{\pi d_{2}^{2}} \, Pa$

$\frac{p_{1}}{p_{2}} = \frac{20.3718 \pi d_{2}^{2}}{4} = 16 d_{2}^{2}$

Because p₁/p₂ = T₁/T₂, therefore
$16d_{2}^{2} = \frac{293}{423} \\\\ d_{2}^{2} = \frac{0.6927}{16} \\\\ d_{2} = 0.2081 \, m$

The minimum piston diameter at 150 C is 20.8 cm.

Answer: 20.8 cm diameter

8 0

3 years ago