Answer:
Physical change
Explanation:
Physical change -
It is the type of reversible change , where there is change in the state of the matter , is referred to as a physical change .
There is no chemical process involved during state change , i.e. , no new substance is formed .
Hence , from the given statement of the question, the correct term is physical change.
An ELEMENT is a substance that cannot be broken down into other substances by ordinary chemical procedures. Some easy examples would be: <span>gold, iron, carbon, </span>hydrogen<span>, </span>oxygen<span>, nitrogen.</span>
Answer:
5.625 grams
Explanation:
Start your equation with what you have been given. Place the units you need in your answer on the right side of the equal sign.
225mg
----------- X ----------- X ------------- = ? g
lb
Now start to fill in your equation and use a conversions to get rid of the units you don't want. Convert mg into grams first. The child's weight (25 lb) is placed over 1 just to get the equation lined up properly so you can see how the units cancel out.
225 mg 1 g 25 lb 5.625 g
--------------- X --------------- X ------------- = ---------------
lb 1000 mg 1 1
The lb on the top and bottom cancel each other out and you are left with just grams. Even though it is over one, that is the same at just 5.625 grams.
Answer:
The dissociation equations for NaBr gives Na+ and Br-
The dissociation equations for ZnCl2 gives Zn2+ and 2 Cl-
Explanation:
The following pictures shows that the dissociation of one particle of NaBr produces one particle of Na+ (sodium cation) and one particle of Br- (bromine anion).
The dissociation of one particle of ZnCl2 produces one particle of Zn+2 (Zinc cation) and two particles of Cl- (chlorine anion).
Carbene is :CH₂ (i.e, methylene) which contains one neutral divalent carbon atom with valency of two and two unshared valence electrons. Carbene is of two types: Singlet carbene and Triplet carbene. Carbenes are very short lived and unstable. It is highly reactive intermediate. General carbene which refers to specific species methylene ( :CH₂) contains two hydrogen atoms. Carbene is one of the very important intermediate of various organic synthesis.
