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3 years ago

The atomic number, or number, is the described as the number of _ in the nucleus of an chemical element.

1 answer:

8 0

The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom. It is identical to the charge number of the nucleus. The atomic number uniquely identifies a chemical element. In an uncharged atom, the atomic number is also equal to the number of electrons.

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gregori [183]

Answer:

they both evaperated bye heat

Explanation:

3 0

4 years ago

A firm receives an order for a square-base rectangular storage container with a lid. The container has a volume of 20 cubic mete

Stels [109]

Answer:$ 506.05

Explanation:

Given

volume of container $=20 m^3$

Let L be the length of square-base and h be the height of Rectangular box

Cost of base $=20 \$/m^2$

Cost of side and lid $=10 \$ /m^2$

Cost of base $c_1=L^2\times 20$

$h=\frac{20}{L^2}$

cost of lid and side $c_2=10\times 4L\cdot h+10\times L^2$

Total cost $C=c_1+c_2$

$C=20L^2+10L^2+40L\cdot h$

$C=30L^2+\frac{800}{L}$

differentiate C w.r.t to L to get minimum cost

$\frac{\mathrm{d} C}{\mathrm{d} L}=60L-\frac{800}{L^2}=0$

$L^3=\frac{80}{6}$

$L=2.37 m$

thus $h=\frac{20}{5.613}=3.56 m$

Thus Lowest cost is $C=30\times 5.617+\frac{800}{2.37}=$ 506.05$

4 0

3 years ago

The total power consumption by all humans on earth is approximately 1013 W. Let’s compare this to the power of incoming solar ra

suter [353]

Answer:

Power coming from solar radiations is 6.94 * 10^14 times higher that the power consumption of all humans.

Explanation:

Intensity of sunlight = I = 1380 w/m^2

Area of earth = A = 4*pi*r^2 = 4*pi*(6.37*10^6)^2 = 5.09*10^14 m^2

he intensity is defined as the total power spread over the area of earth (Area of Sphere with radius equal to distance between earth and sun) and given by the following formula:

Intenity of sunlight = Power/Area of earth

I = P/A

P = IA

P = (1380)(5.09*10^14)

P = 7.036*10^17 W

if we take ratio:

7.036*10^17/1013 = 6.94 * 10^14

Hence, power coming from solar radiations is 6.94 * 10^14 times higher that the power consumption of all humans.

5 0

3 years ago

Which compound is most likely a powerful and dangerous acid? H2S HBr Li2O LiBR

sattari [20]

HBr is the most powerful and dangerous acid .

Explanation:

A strong acid is one that instantly disunites or grants its protons in suspension. HBr is a strong acid. HBr is powerful than HCl or HF because the overlapping of a 1s-orbital and a 4p-orbital is surprisingly small, thus the binding is weak so splitting is very easy..

6 0

4 years ago

Read 2 more answers

1. In a demonstration, Mr. K stretches a steel wire to a length 1.23 meters and braces both ends so that they are not free to vi

BaLLatris [955]

Answer:

a.241.08 m/s b. 196 Hz c. 392 Hz

Explanation:

a. Determine the speed of waves within the wire.

The frequency of oscillation of the wave in the string, f = nv/2L where n = harmonic number, v = speed of wave in string, L = length of string = 1.23 m.

Since f = 588 Hz which is the 6 th harmonic, n = 6. So, making v subject of the formula, we have

v = 2Lf/n

substituting the values of the variables into v. we have

v = 2 × 1.23 m × 588Hz/6

v = 241.08 m/s

b. Determine the frequency at which the wire will vibrate with the first harmonic wave pattern.

The first harmonic is obtained from f when n = 1,

So, f = v/2L = 241.08 m/s ÷ 1.23m = 196 Hz

c. Determine the frequency at which the wire will vibrate with the second harmonic wave pattern.

The second harmonic f' = 2f = 2 × 196 Hz = 392 Hz

5 0

3 years ago

The atomic number, or ________ number, is the described as the number of _________ in the nucleus of an chemical element.

The atomic number, or number, is the described as the number of _ in the nucleus of an chemical element.