your answer is <u>D</u><u>.</u><u> </u>physical change, because a new substance is not formed.
Answer:
d) Cr⁺³
Explanation:
Consideremos un ion que contiene 24 protones, 28 neutrones y 21 electrones.
Para encontrar el simbolo del elemento, tenemos que considerar el número atómico (Z) que es igual al número de protones. Con esta información, buscamos en la tabla periódica el elemento con Z=24 es el Cromo.
La carga total está dada por la diferencia entre protones y electrones. Los ´protones tienen carga +1 y los electrones carga -1. Luego, este ion tiene carga:
24 protones + 21 electrones = 24 . (1) + 21 . (-1) = +3
El simbolo del ion es Cr⁺³.
Answer:
Alkali metal hydroxides can be used to test the identity of metals in certain salts. The colour of the precipitate will help identify the metal : Calcium hydroxide is soluble; no precipitate is formed.
We measure temperature in degrees of Fahrenheit
Atoms are fundamental constituents of all matter. The following statement is correct. The nucleus always has a positive charge. This is because the nucleus contains sub-atomic particles called protons. Each proton carries a single positive charge. The nucleus is also home to sub-atomic particles called neutrons that do not possess a charge.
