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2 years ago

C. Another radioisotope of americium exists which has an atomic mass of 242.

Chemistry

1 answer:

ollegr [7]2 years ago

7 0

Answer:

1 g

Explanation:

The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.

We can make a table of the mass left after each half-life.

$\begin{array}{cccc}\textbf{No. of} & & \textbf{Percent} & \textbf{Mass}\\\textbf{Half-lives} & \textbf{Time/h} & \textbf{Remaining} & \textbf{Remaining/g}\\0& 0 & 100 & 8\\1 & 16 &50 & 4\\2 & 32 & 25 & 2\\3 & 48 & 12.5 & 1\\4 & 64 & 6.25 & 0.5\\\end{array}$

The mass remaining after 48 h is 1 g.

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Putting rock salt on the roads during a snowstorm is an example of: A. Boiling point elevation B. Vapor pressure raising C. Vapo

kvv77 [185]

Answer:

The correct answer is - D. Freezing point depression.

Explanation:

When rock salt is spread over snow-covered icy roads, it generates a liquid layer over it by melting from the surface thereby lowering or depression in the freezing point below the ice.

Therefore, due to this liquid layer comes into the contact with the ice present on the road and causes other ice to melts. This keeps on decreasing the volume of the ice on the road therefore, rock salts spread on the roads during a snowstorm.

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2 years ago

What does cpd in organic chemistry mean?

makvit [3.9K]

It means a substance formed by chemical union of 2 or more elements or ingredients in definite proportion by weight.

4 0

2 years ago

In an ion with an unknown charge, the total mass of all the electrons was determined to be 2.19 ✕ 10−26 g, while the total mass

Ilya [14]

Answer:

$\large \boxed{\text{Fe$^{{2+}}$}}$

Explanation:

1. Number of electrons

$\text{Number of electrons} = 2.19 \times 10^{-26}\text{ g} \times \dfrac{\text{1 electron}}{9.109 \times 10^{-28}\text{ g}} = \text{24 electrons}$

2. Number of protons

$\text{Number of protons} = 4.34 \times 10^{-23}\text{ g} \times \dfrac{\text{1 proton}}{1.673 \times 10^{-24}\text{ g}} = \text{26 protons}$

3. Identify the ion

An atom with 26 protons is iron, Fe.

A neutral atom of iron would have 26 electrons.

The ion has only 24 electrons, so it has lost two. The ion must have a charge of +2.

$\text{The symbol for the ion is $\large \boxed{\textbf{Fe$^{\mathbf{2+}}$}}$}$

4 0

2 years ago

Hydrogen bromide is found in volcanic gas. What is the chemical formula for this compound?

ruslelena [56]

Answer:

Hydrogen bromide, anhydrous appears as a colorless gas with a pungent irritating odor. Corrosive. Heavier than air. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Long-term exposure to low concentrations or short-term exposure to high concentrations can result in adverse health effects from inhalation. Used to make other chemicals and as a catalyst in the manufacture of chemicals. Rate of onset: Immediate Persistence: Minutes to hours Odor threshold: 2 ppm Source/use/other hazard: Chemical manufacturing industry; very corrosive.

Explanation:

HBr

3 0

2 years ago

Read 2 more answers

Assume the pH of household bleach is 12. What is the hydronium ion concentration in household bleach? What is it hydroxide ion c

Ostrovityanka [42]

Answer:

[H3O+] = 1.0*10^-12 M

[OH-] = 0.01 M

Explanation:

We can use the following equation to find the hydronium ion concentration. Plug in the pH and solve for H3O+.

pH = -log[H3O+]

[H3O+] = 1.0*10^-12 M

Now, to find the hydroxide ion concentration we will use the two following equations.

14 = pH + pOH

pOH = -log[OH-]

14 = 12 + pOH

pOH = 2

2 = -log[OH-]

[OH-] = 0.01 M

8 0

2 years ago