Answer:
Ion exchange.
Explanation:
One of the ways in which water can be treated is through the process known as ION EXCHANGE. Using this for treating water has to do basically with the transfer or say the exchange of ions.
Ion exchanges is done by exchanging ions which are considered as 'unfit' or contaminants by the ones that are "fit".
Ions from what is known as zeolite or resin is been exchanged with the ions in the water. Cations are exchanged with cations and anions are exchanged with anions.
NB: this method is a good method or removing contaminants that are ions but not contaminants that are not ions.
Answer: option A.
A physical change occurred in which the iron remained iron, but lost one of its physical properties
Explanation: magnetization and demagnetization is a physical change as no new substance is form and it is easily reversed. When an iron rod is magnetized, it can loss it magnetic property by hitting it. So when an iron rod which is magnetized falls from a height it can also loss its magnetic property
Answer:
B
Explanation:
Light travels faster than sound.
Answer:
The correct answer is option D which is the decreasing order of conductivity is Mn, O, Ge.
Explanation:
You can easily answer this if you know the periodic trends. For the property of electrical conductivity, it decreases across a period and decreases also down a group. Thus, the most conductive element must be Mn, while the least conductive one is Ge. So, the answer is: -Mn, O, Ge
Answer:
About 16.1 grams of oxygen gas.
Explanation:
The reaction between magnesium and oxygen can be described by the equation:
24.4 grams of Mg reacted with O₂ to produce 40.5 grams of MgO. We want to determine the mass of O₂ in the chemical change.
Compute using stoichiometry. From the equation, we know that two moles of MgO is produced from every one mole of O₂. Therefore, we can:
- Convert grams of MgO to moles of MgO.
- Moles of MgO to moles of O₂
- And moles of O₂ to grams of O₂.
The molecular weights of MgO and O₂ are 40.31 g/mol and 32.00 g/mol, respectively.
Dimensional analysis:
In conclusion, about 16.1 grams of oxygen gas was reacted.
You will obtain the same result if you compute with the 24.4 grams of Mg instead:
