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3 years ago

Please help me. ? :)

Chemistry

1 answer:

BaLLatris [955]3 years ago

3 0

Answers and explanation:

To answer these questions you use a periodic table.

A is In because it has 49 protons and In is element number 49.

B is 27 because Co is element number 27.

C is 73 because Ta is element number 73.

D is 49 because the number of electrons in an atoms is always equal to the number of protons.

E is 56 because the atomic number of Ba is 56.

F is 54 because 56 - 54 = 2. The charge is equal to the number of protons minus the number of electrons.

G is 66. The number of neutrons is equal to the atomic mass minus the number of protons. 115 - 49 = 66.

H is 108 because 181 - 73 = 108.

I is 32. The atomic mass of an element is equal to the amount of protons plus the amount of neutrons. So 16 + 16 = 32.

You might be interested in

A. Lithium iodide and bromine react to produce lithium bromide and iodine.

Gelneren [198K]

2LiI+1Br₂-->2LiBr+1I₂

1CsNO₃+1KCl-->1CsCl+1KNO₃

4 0

3 years ago

Which elements are out of order in terms of atomic mass. co,Ni or Li,be or I,xe

valkas [14]

Answer:

The pair co,Ni is out of order in terms of atomic mass

Explanation:

For co,Ni

Atomic mass of Co = 58.9331 u

Atomic mass of Ni = 58.6934

For Li,be

Atomic mass of Li = 6.941 u

Atomic mass of be = 9.012182 u

For I,xe

Atomic mass of I = 126.90447 u

Atomic mass of Xe = 131.293 u

Hence, the pair co,Ni is out of order in terms of atomic mass

7 0

3 years ago

Which of the five most abundant elements are metals?

Gala2k [10]

Answer:

Oxygen

Silicon

Aluminium

Iron

Calcium

Explanation:

Oxygen=47 percent

Silicon=28 percent

Aluminium=8 percent

Iron=5 percent

Calcium=3.5 percent

Hope it helps :)

Mark me as brainliest

6 0

3 years ago

Need help <br>1/6 + 1/8 =

pogonyaev

1/6 + 1/8 = 7/24

≅ 0.2916667

6 0

3 years ago

Consider the equilibrium reaction and its equilibrium constant expression. Br 2 ( g ) + 2 NO ( g ) − ⇀ ↽ − 2 NOBr ( g ) K = [ NO

zavuch27 [327]

Answer:

$K_2=\frac{[NOBr]^4_{eq}}{[NO]^4_{eq}[Br]^2_{eq}}$

Explanation:

Hello,

In this case, for the equilibrium condition, the equilibrium constant is defined via the law of mass action, which states that the division between the concentrations of the products over the concentration of the reactants at equilibrium equals the equilibrium constant, for the given reaction:

$2 Br_2 ( g ) + 4 NO ( g ) \rightleftharpoons 4NOBr ( g )$

The suitable equilibrium constant turns out:

$K_2=\frac{[NOBr]^4_{eq}}{[NO]^4_{eq}[Br]^2_{eq}}$

Or in terms of the initial equilibrium constant:

$K_2=K_1^2$

Since the second reaction is a doubled version of the first one.

Best regards.

5 0

3 years ago