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3 years ago

What is an environmental hazard created by humans?

1 answer:

5 0

Environmental Hazards are usually any chemicals that donot naturally occur to exist anywhere and are usually made in the fields of industry or experimental sciences
So if you happen for example to throw a bit of mercury in some river while being in a school trip then this is an environmental hazard created by humans

You might be interested in

How many atoms are in one body-centered cubic unit cell of a metal?

Mashcka [7]

Answer:

Option B - 2

Explanation:

In Crystal lattices, there are different types of unit cells namely;

- Hexagonal Closest Packed (HCP)

- Face Centred Cubic (FCC)

- Body Centred Cubic (BCC)

- Simple Centred Cubic (SC)

Now, each of them have a coordination number and also number of atoms per unit cell.

For this question, we are restricted to the body-centered cubic (bcc) unit cell which has a coordination number of 8 and contains 2 atoms per unit cell.

3 0

3 years ago

How many litres of fluorine gas at stp can be collected from the decomposition of 90.7 g of AuF3

7nadin3 [17]

Answer: 12 L fluorine gas at STP can be collected from the decomposition of 90.7 g of $AuF_3$

Explanation:

The balanced decomposition reaction is shown as

$2AuF_3\rightarrow 2Au+3F_2$

moles of $AuF_3=\frac{\text {given mass}}{\text {Molar mass}}=\frac{90.7g}{254g/mol}=0.36moles$

According to stoichiometry:

2 moles of $AuF_3$ gives = 3 moles of flourine gas

Thus 0.36 moles of $AuF_3$ gives = $\frac{3}{2}\times 0.36=0.54moles$ of flourine gas

Using ideal gas equation :

$PV=nRT$

P = pressure of gas = 1 atm ( at STP)

V = Volume of gas = ?

n = moles of gas = 0.54

R = gas constant = 0.0821 L atm/Kmol

T = temperature = 273 K ( at STP)

Putting the values we get :

$1atm\times V=0.54mol\times 0.0821Latm/Kmol\times 273K$

$V=12L$

Thus 12 L fluorine gas at STP can be collected from the decomposition of 90.7 g of $AuF_3$

6 0

3 years ago

A gas has a volume of 25 ml, at a pressure of 1 atmosphere (1 atm). Increase the volume to 125 ml and the temperature remains co

vekshin1

Explanation:

The new pressure can be found by using the formula for Boyle's law which is

$P_1V_1 = P_2V_2 \\$

Since we're finding the new pressure

$P_2 = \frac{P_1V_1}{V_2} \\$

We have

$P_2 = \frac{25 \times 1}{125} = \frac{25}{125} = \frac{1}{5} = 0.2 \\$

We have the final answer as

Hope this helps you

8 0

3 years ago

The three nuclides, U-233, U-235, and U-238, are isotopes of uranium because they have the same number of protons per atom and A

snow_tiger [21]

Answer:

The correct answer is - C) a different number of neutrons per atom.

Explanation:

Isotopes of an element are the same element and same atomic number but with different atomic mass and physical properties. The difference in their atomic mass occurs due to isotopes of an element have a different number of neutrons per atom.

The number of protons and the numbers of electrons are the same in the isotopes but only change occurs in the numbers of the neutrons. In isotopes of uranium U-233, U-235, and U-238 have the same number of protons but a different number of neutrons per atom.

3 0

3 years ago

Analysis of a 10.15 g sample of a compound known to contain only phosphorus and oxygen indicates a phosphorus content of 4.433 g

Anna007 [38]

find mass of oxygen by subtracting mass of phosphorus from the total mass

divide the masses by the molar mass to get moles

divide moles by the smallest amount of moles

multiply by 2 to get a nice number

P4O5

5 0

3 years ago