Atoms are real even though they're invisible.
Answer:
Mira la explicación.
Explanation:
¡Hola!
En este caso, podemos encontrar facilmente el grupo al que pertenecen dichos elementos con números atómicos 8, 36 y 39 respectivamente mediante su búsqueda en la tabla periódica. Así, z=8 corresponde a oxígeno, z=36 a kriptón y z=39 a itrio.
Por otro lado, para saber el número de capas, debemos desarrollar la configuración electrónica para cada uno:

Con esto, vemos que oxígeno tiene dos capas, kripton cuatro capas e iritrio cinco, a lo que a oxígeno le faltan dos electrones para llenar dicha capa, a kripton ninguno y a iritrio nueve.
Saludos.
I think there would be two correct answers from the choices listed above. These are the second and the last option. Composites are strong and elastic because of the extensive cross-linking between molecules and the <span>properties of metals and plastics. Hope this answers the question.</span>
Answer: 
Explanation:
Heat of combustion is the amount of heat released when 1 mole of the compound is completely burnt in the presence of oxygen.

To calculate the moles, we use the equation:
Thus
of sucrose releases = 916.6 J of heat
1 mole of sucrose releases =
of heat
Thus ∆H value for the combustion reaction is 
Answer:
It is written exactly like that; Mg3N2
Explanation:
Roman numerals are used sometimes to show the charge of an ion that can be multiple charges.