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4 years ago

15

A radioactive nuclide that is used for geological dating has an atomic number of 19 and mass number 40. Which is the symbol of t

his nuclide?

2 answers:

Alina [70]4 years ago

7 0

The mass number goes on top, and the atomic number goes on bottom.
Therefore, the answer is C:
40
K
19

aleksklad [387]4 years ago

3 0

Answer:

C. 40/19 K

Explanation:

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156. A solid metal sphere has a volume of 4.2 ft}. The mass

snow_tiger [21]

Answer:

The answer is

<h2>0.59 g/cm³</h2>

Explanation:

To find the density of the sphere we use the formula

<h2> $Density \: = \frac{mass}{volume}$ </h2>

To find the density in g/cm³ first convert the mass into grams and the volume into cm³

For the mass we have

155 lb = 70306.82 g

For the volume

4.2 ft³ = 118930.76 cm³

Substitute the values into the above formula

That's

<h2> $Density \: = \frac{70306.82 \: g}{118930.76 \: cm³}$ </h2>

We have the final answer as

<h3>Density = 0.59 g/cm³</h3>

Hope this helps you

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4 years ago

Need boy who is at leaast 12

Dahasolnce [82]

Answer:

helloo!!!!!!! I am 12 :)

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3 years ago

If have a volume of 18 L of a gas at a temperature of 272 K and a pressure of 90 atm, what will be the pressure of the gas if ra

Solnce55 [7]

Answer:

P₂ ≅ 100 atm (1 sig. fig. based on the given value of P₁ = 90 atm)

Explanation:

Given:

P₁ = 90 atm P₂ = ?

V₁ = 18 Liters(L) L₂ = 12 Liters(L)

=> decrease volume => increase pressure

=> volume ratio that will increase 90 atm is (18L/12L)

T₁ = 272 Kelvin(K) T₂ = 274 Kelvin(K)

=> increase temperature => increase pressure

=> temperature ratio that will increase 90 atm is (274K/272K)

n₁ = moles = constant n₂ = n₁ = constant

P₂ = 90 atm x (18L/12L) x (274K/272K) = 135.9926471 atm (calculator)

By rule of sig. figs., the final answer should be rounded to an accuracy equal to the 'measured' data value having the least number of sig. figs. This means P₂ ≅ 100 atm based on the given value of P₁ = 90 atm.

3 0

3 years ago

Write a balanced nuclear equation for the beta decay of carbon-11.

timofeeve [1]

In balancing nuclear decay types of reaction, the same as balancing a chemical reaction, we use the number and the type of nucleons present for the decay reaction. Regardless of the type of decay, it should be that the total number of nucleons in the shole process should be conserved. For carbon-11, the decay equation would be as follows:
11/6 C --->11/5 B + 0/1β
It is an example of a positron emmision or a positive beta decay. It is a decay for neutron-poor nuclei where a proton is being transformed into a neutron and also emitting a positron that is high in energy.

8 0

4 years ago

Read 2 more answers

A mixture of neon and methane gases, in a 8.53 L flask at 72 °C, contains 1.56 grams of neon and 4.85 grams of methane. The part

Yanka [14]

Answer:

The partial pressure of methane in the flask is 1.00 atm and the total pressure in the flask is 1.26 atm.

Explanation:

You must apply the Ideal Gases Law to solve this;

Pressure . volume = n° moles . Gases constant (R) . T° in K

T° in K = T°C + 273

72 + 273 = 345K

Gases constant (R) = 0.082 L.atm /mol.K

n° moles = in mixture, the total moles are the sum of each gas.

Moles = mass / molar mass

Moles Ne = 1.56 g / 20.17 g/m = 0.077 moles

Moles CH₄ = 4.85 g/ 16.04 g/m = 0.302 moles

0.077 + 0.302 = 0.379 moles

Pressure . 8.53L = 0.379 moles . 0.082 L.atm /mol.K . 345K

Pressure = ( 0.379 moles . 0.082 L.atm /mol.K . 345K ) / 8.53L

Pressure = 1.26 atm (The total pressure in system)

We can use the molar fraction to know, the partial pressure of CH₄.

Moles CH₄ / Total moles = Partial pressure CH₄ / Total pressure

0.302 / 0.379 = Partial pressure CH₄ / 1.26 atm

(0.302 / 0.379 ) . 1.26 atm = Partial pressure CH₄

1.00 atm = Partial pressure CH₄

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3 years ago