Answer:
What type of reaction is shown below? Check all that apply.
Ca + 2H2O → Ca(OH)2 + H2
synthesis
decomposition
combustion
single replacement
double replacement
Explanation:
Weathering and chemical substance weathering
For the reactants,
- The oxidation number of hydrogen = +1
- The oxidation number of oxygen = -2
- The oxidation number of arsenic = +5
- The oxidation number of carbon = +3
For the products,
- The oxidation number of hydrogen = +1
- The oxidation number of oxygen = -2
- The oxidation number of arsenic = +3
- The oxidation number of carbon = +4
Here, arsenic (+5 to +3) and carbon (+3 to +4) are the only oxidation numbers changing.
Note that an increase in oxidation number means electrons are lost. Thus oxidation is occurring, and a decrease in oxidation number means electrons are being gained, and thus reduction is occurring.
Also, the compound that contains the element being oxidized is the reducing agent, and the compound that contains the element being reduced is the oxidizing agent.
So, the answers are:
name of the element oxidized: Carbon
name of the element reduced: Arsenic
formula of the oxidizing agent: 
formula of the reducing agent: 
Every isotope of an element has a different number of neutrons, which means that the atomic property which is different in each isotope of an element is mass number.
Mass number depends on the number of neutrons in an element.
Answer:
1. The Earth's orbit around the Sun is an ellipse, but it does change shape. ...
The tilt in the axis of the Earth is called its obliquity
Explanation:
2.Volcanic eruptions pump out clouds of dust and ash, which block out some sunlight.