Answer:
Manganese (Mn)
Explanation:
We know it's manganese because we are told it is an electrically neutral atom. This means it has the same number of protons and electrons. If it has 25 electrons, it has 25 protons. Protons tell us the atomic number of the atom, which also tells us the name of the element. Manganese is element 25 on the periodic table.
Answer:
Acid - A compound that increases hydrogen ions (H+) when it is dissolved in a solution
pH - A value from 0 to 14 that is used to specify how acidic or basic a compound is when it is dissolved in water
Base - A compound that increases hydroxide ions (OH−) when it is dissolved in a solution
Litmus paper - Used to measure the pH of substances by determining their hydrogen ion concentration
Answer:
The decomposition of ethane is 153.344 times much faster at 625°C than at 525°C.
Explanation:
According to the Arrhenius equation,
where,
= rate of reaction at
= rate of reaction at
= activation energy of the reaction
R = gas constant = 8.314 J/K mol
The decomposition of ethane is 153.344 times much faster at 625°C than at 525°C.
The electron B. is the smallest part of an atom.
Answer:
concentration of bromide (Br⁻) = 4234 mg/L = 4234 ppm
Explanation:
ppm (parts per million) concentration is defined as the mass (in milligrams) of a substance dissolved in one liter of solution.
In our case we have:
mass of MgBr₂ = 12.41 g
volume of water (which is equal to the final solution volume) = 2.55 L
Now we devise the following reasoning:
if 12.41 g of MgBr₂ are dissolved in 2.55 L of water
then X g of MgBr₂ are dissolved in 1 L of water
X = (1 × 12.41) / 2.55 = 4.867 g of MgBr₂
if in 184 g (1 mole) of MgBr₂ we have 160 g of Br⁻
then in 4.867 g of MgBr₂ we have Y g of Br⁻
Y = (4.867 × 160) / 184 = 4.232 g of bromide (Br⁻)
4.232 g of bromide (Br⁻) = 4234 mg of bromide (Br⁻)
concentration of bromide (Br⁻) = 4234 mg/L = 4234 ppm