A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds. Elements: are pure substances made up of only l type of atom. Atoms of the same element are identical in properties.
Answer:
N2H2(aq) + 2OH^-(aq) ----------> N2(g) + 2H2O(l) + 2e
Explanation:
Hydrazine is mostly used in thermal engineering as an anticorrosive agent. Hydrazine can be oxidized in aqueous solution as shown in the equation above. Oxidation has to do with loss of electrons and increase in oxidation number.
The oxidation number of nitrogen in the equation increased from -1 in hydrazine on the lefthand side of the reaction equation to zero in nitrogen on the right hand side of the reaction equation. Two electrons were lost in the process as shown.
BIOLOGICAL & CHEMICAL EVIDENCE ANALYSIS
There are many different types of evidence that can be found at a crime scene. Physical evidence can be collected at the crime scene such as a murder weapon. Chemical evidence is any residue from liquids that such as poison and drugs. Biological evidence is when hair or skin from a persons body has been transferred to a physical surface and then be collected and tested.
This evidence can be used to find out what exactly happened at the scene of the crime, the history behind the crime and who was involved and could have committed it.
Our experts test and analyse many forms of evidence, which is vital when finding out the various incidences that happened at a crime scene.
Explanation:
calculate the frequency of a wave
Answer:
Explanation:
Hygrometer, instrument used in meteorological science to measure the humidity, or amount of water vapour in the air. Several major types of hygrometers are used to measure humidity.
