Answer:
Poaching.
Explanation:
The descriptions for each of the terms you listed:
- poaching: illegal hunting of wild animals
- habitat destruction: the process in which a habitat becomes unsuitable for supporting life, often by human activity
- pollution: the introduction of hazardous or harmful waste into the environment
- nonnative species: a species introduced to a new habitat, often by human activity, that thrives unusually well due to having no natural predators in its new habitat.
Hunting elephants (an illegal activity in many countries) for their ivory is considered poaching.
1) we calculate the molar mass of He (helium) and Kr (Krypton).
atomic mass (He)=4 u
atomic mas (Kr)=83.8 u
Therefore the molar mass will be:
molar mass(He)=4 g/mol
molar mass(Kr)=83.8 g/mol.
1) We can find the next equation:
mass=molar mass x number of moles.
x=number of moles of helium
y=number of moles of helium.
(4 g/mol) x +(83.8 g/mol)y=103.75 g
Therefore, we have the next equation:
(1)
4x+83.8y=103.75
2) We can find other equation:
We have 30% helium atoms and 70% Kryptum atoms, therefore we have 30% Helium moles and 70% of Krypton moles.
1 mol is always 6.022 * 10²³ atoms or molecules, (in this case atoms).
Then:
x=number of moles of helium
y=number of moles of helium.
(x+y)=number of moles of our sample.
x=30% of (x+y)
Therefore, we have this other equation:
(2)
x=0.3(x+y)
With the equations(1) and (2), we have the next system of equations:
4x+83.8y=103.75
x=0.3(x+y) ⇒ x=0.3x+0.3y ⇒ x-0.3x=0.3y ⇒ 0.7 x=0.3y ⇒ x=0.3y/0.7
⇒x=3y/7
We solve this system of equations by substitution method.
x=3y/7
4(3y/7)+83.8y=103.75
lower common multiple)7
12y+586.6y=726.25
598.6y=726.25
y=1.21
x=3y/7=3(1.21)/7=0.52
We have 0.52 moles of helium and 1.21 moles of Krypton.
1 mol=6.022 * 10²³ atoms
Total number of particles=(6.022 *10²³ atoms /1 mol) (number of moles of He+ number of moles of Kr).
Total number of particles=6.022 * 10²³ (0.52+1.21)=6.022 * 10²³ (1.73)=
=1.044 * 10²⁴ atoms.
Answer: The sample have 1.044 * 10²⁴ atoms.
Answer:
Some indicators of rusting include:
a. color change
b. formation of as solid
Explanation:
Rusting is a redox ( a reaction in which reduction and oxidation occur concurrently) reaction which occcur when metallic iron is exposed to air and water or water vapor reacts with the oxygen and water to form a hydrated mixture of oxides of the metal.
The shiny metallic iron becomes oxidized to Fe²⁺ and Fe³⁺ ions while neutral oxygen gas molecules are reduced to O²⁻ ions. The shiny metallic iron also loses its lustrous appearance as the process proceeds and is covered by a layer of rust.
The equation for reaction is given below:
4Fe(s) + 30₂(g) + xH₂O(l) -----> 2Fe₂O₃. xH₂O(s)
The product of the reaction above is known as rust and is reddish-brown solid.
Rusting causes iron to become flaky and weak as rust is very light and porous, reducing the strength and appearance of iron which are desirable properties of iron when used in construction. The rusting of iron can lead to damage to automobiles, railings, bridges, and several other iron structures.
<h3>What is
Self-Consistent Field (SCF)?</h3>
This is used in quantum chemical models to accurately calculate the amount
of orbitals present in an element.
The Self-Consistent Field (SCF) method for obtaining the orbitals of a
Boron atom involves the following processes which include:
- Selecting an approximate Hamiltonian
- Solving the Schrödinger equation to obtain a more accurate set of orbitals.
- Solving the Schrödinger equation again until the results converge.
The converging of the result typically signified the end of the solving of the
equations and the derivation of the orbitals of the Boron atom.
Read more about Orbitals here brainly.com/question/26000020
