Responder:
27
Explicación:
Dado que:
Número de protones en el átomo X = 29
Carga en el átomo X = +2
Si no hay cargo neto;
número de protones = número de electrones
Sin embargo, dado que el átomo X tiene una carga de +2 (dando 2 electrones).
Por lo tanto,
Número de electrones = número de protones - número de carga en el átomo)
Número de electrones = (29 - 2) = 27
Answer: northern hemisphere
Explanation: I looked it up. Plus I took a test with this question and when the teacher went over the answer i got it right.
The percentage of Chromium in Chromium Oxide is calculated as follow,
Step 1: Calculate Molar mass of Cr₂O₃,
Cr = 51.99 u
O = 16 u
So,
2(51.99) + 3(16) = 103.98 + 48 = 151.98 u
Step 2: Secondly divide molar mass of only chromium with total mass of Cr₂O₃ and multiply with 100.
i.e.
=
× 100
=
68.41 %
So, the %age composition of chromium in chromium oxide is
68.41 %.
Answer:
chemical energy, Energy stored in the bonds of chemical compounds. Chemical energy may be released during a chemical reaction, often in the form of heat; such reactions are called exothermic.
18. Reaction will occur.
19. Reaction Will occur.
20. Reaction will occur.
21. Reaction will occur.
22. Reaction won't occur.
23. Reaction will occur.
24. Reaction will occur.
25. Reaction won't occur.
<h3><u>Explanation</u>:</h3>
The reaction rate of the metals with water, steam, acid, or hydroxides or their inert behavior towards them are noted in the metal activity series.
It contains all the metals one after the other which and the upper metal can replace the lower metal from its salt.
Calcium can replace hydrogen from acid, so the reaction will occur in 18. The products formed are calcium phosphate and hydrogen gas.
Chlorine is more reactive than bromine. So it can replace bromine from its salt to from bromine gas and magnesium chloride.
Aluminium can replace iron from its salt. So it will form aluminium oxide and iron metal. This reaction is used to obtain iron from ores.
Zinc can replace hydrogen from acid. So the products will be zinc chloride and hydrogen gas.
Chromium cannot displace hydrogen form water. So the reaction won't occur.
Tin can replace hydrogen form acid. So the reaction will proceed.
Magnesium will replace platinum from its salt. So magnesium oxide and platinum will form.
Bismuth cannot replace hydrogen from acid. So the reaction won't proceed.
