Answer:
A. there is an isotope of lanthanum with an atomic mass of 138.9
Explanation:
By knowing the different atomic masses of both Lanthanum atoms, we can not tell anything about their occurence in nature. Therefore, all the last three options are incorrect. Because, the atomic mass does not tell anything about the availability or natural abundance of an element.
Now, the isotopes of an element are those elements, which have same number of electrons and protons as the original element, but different number of neutrons. Therefore, they have same atomic number but, different atomic weight or atomic masses.
Hence, by looking at an elements having same atomic number, but different atomic masses, we can identify them as isotopes.
Thus, the correct option is:
<u>A. there is an isotope of lanthanum with an atomic mass of 138.9.</u>
the number of protons in the atomic nucleus
The answer is 20N as when the object is accelerating at 3 m/s2 it as a force of 10N applied to it so to get to 6m/s2 3(x2) = 6 so 10(x2) = 20
Answer:
D. ionic sodium phosphate (Na3PO4)
Explanation:
Molecule for molecule, the solute that raises the boiling point of water the most is the one that makes the most particles in the solution. Lithium chloride breaks up into two ions (Li+ and Cl-). So does sodium chloride (Na+ and Cl-). Molecular molecules don't break up at all, so sucrose has only 1 particle per molecule. Sodium phosphate makes 4 total particles (3 Na+ ions and 1 PO4^3-). And magnesium bromide would make 3 particles (1 Mg2+ and 2 Br-). So the most is 4.
Algunas acciones viables para utilizar los recursos ambientales de forma racional y con el objetivo de reducir la contaminación son:
- Reducir, reciclar y reutilizar los residuos generados en el hogar.
- Reducir el uso de vehículos de combustión interna.
- No quemes basura al aire libre
- No utilices aerosoles ni frigoríficos que dañen la capa de ozono.
<h3 /><h3>¿Qué importancia tiene la sostenibilidad?</h3>
Es fundamental para la preservación y mantenimiento del medio ambiente y la calidad de vida de las generaciones actuales y futuras. El desarrollo de acciones sostenibles promueve la protección del medio ambiente, los ecosistemas y los recursos naturales.
Por lo tanto, todas las personas e instituciones económicas pueden promover la sostenibilidad a través de prácticas fáciles de ejecutar que ayuden a preservar y proteger el medio ambiente.
Encuentre más información sobre sostenibilidad aquí:
brainly.com/question/23701037