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3 years ago

Which element is a gas? A.Br B.C C.B D.Be

Chemistry

2 answers:

Kisachek [45]3 years ago

8 0

Answer:

A.Br

Explanation:

Bromine is the only gas from the choices provided. It belongs to the group of halogens, group 7.

It has atomic number of 35 and it belongs to the p-block on the periodic table.

C is carbon and carbon is a solid matter
B is boron and boron is a metalloid
Be is beryllium and silvery white metal

Only Bromine is the gas from the given choices. It is fuming liquid and when exposed, it becomes gaseous.

Gala2k [10]3 years ago

7 0

The answer should be (B) C

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This is an incomplete question, here is a complete question.

Calculate the pH of a solution made by adding 59 g of sodium acetate, NaCH₃COO, to 23 g of acetic acid, CH₃COOH, and dissolving in water to make 400. mL of solution. Hint given in feedback. The Ka for CH₃COOH is 1.8 x 10⁻⁵ M. As usual, report pH to 2 decimal places.

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$pH=4.7+\log (\frac{0.719}{0.383})$

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