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Is it correct to say the chemical changes are not reversible but physical changes are?
yes it is correct because chemical energy means you can't change something back like paper if you burned that paper you can't change it back but if you had that paper and you ripped it you can glue it back you can fix it that is physical energy when you can put something back together so yes you can say that.
What else can I help you with?
Is it wrong to say a chemical change is irreversible while physical change is reversible?
Simplistically speaking, the statement is true - not wrong/false. For example, one physical change is to fold paper. After the paper is folded, you can rather effectively unfold it and return it to its original condition. One chemical change is to burn something. After paper is burned, the ashes cannot be "unbunrt" back into paper. However, some chemical changes are reversible. For example, photosynthesis is a chemical change in which water, carbon dioxide, and energy are turned into oxygen and sugars. Respiration is a chemical process in which oxygen and sugars are converted back into water, carbon dioxide, and energy. However, the process of respiration is much more complex than photosynthesis and is not the "reverse" of it, i.e. respiration is non un-photosynthesis.
What does physical and chemical change have in common?
A physical change to an object is a change in properties not involving the chemical makeup. In other words, a physical change is any change you can make to an object without changing the actual substance. (I.e. state of matter, size, shape, color . . .etc.) A chemical change is a change that forms a new substance through a chemical reaction. A chemical reaction is often signaled by bubbling or fizzing, but the only real way to prove a chemical reaction is by coming up with a new substance. So physical changes leave you with the same substance (slightly altered in appearance/texture etc.), but chemical reactions give you a new substance.
Why dissolution of NaCl in water is a physical change not a chemical change?
It has been argued whether this is a chemical or physical change. It can be viewed as a chemical change since the Na ion and Cl ion are separated from the crystal lattice, and then become hydrated by water molecules, thus changing the actual chemical structure. However, this is a REVERSIBLE chemical change. Thus, if you evaporate the water, you end up with the same crystalline structure (lattice) that you began with, and so it may now be viewed as simply a physical change. There is no consensus as to which is correct, IMHO.
A physical change is a change in size shape or state of matter?
Yes, that is correct. A physical change is a change in a substance that does not involve changing its chemical composition. This can include changes in size, shape, or state of matter without altering the substance's fundamental makeup.
If you chop wood for a fire and then burn the wood you have made both physical and chemical changes.?
Chopping wood for a fire is a physical change because the wood's size and shape are altered. Burning the wood is a chemical change because it undergoes a chemical reaction to produce heat, light, and other byproducts.
Is it wrong to say a chemical change is irreversible while physical change is reversible?
Simplistically speaking, the statement is true - not wrong/false. For example, one physical change is to fold paper. After the paper is folded, you can rather effectively unfold it and return it to its original condition. One chemical change is to burn something. After paper is burned, the ashes cannot be "unbunrt" back into paper. However, some chemical changes are reversible. For example, photosynthesis is a chemical change in which water, carbon dioxide, and energy are turned into oxygen and sugars. Respiration is a chemical process in which oxygen and sugars are converted back into water, carbon dioxide, and energy. However, the process of respiration is much more complex than photosynthesis and is not the "reverse" of it, i.e. respiration is non un-photosynthesis.
Is making jam a chemical change?
Yes, because several chemical reactions can occur.
What does physical and chemical change have in common?
A physical change to an object is a change in properties not involving the chemical makeup. In other words, a physical change is any change you can make to an object without changing the actual substance. (I.e. state of matter, size, shape, color . . .etc.) A chemical change is a change that forms a new substance through a chemical reaction. A chemical reaction is often signaled by bubbling or fizzing, but the only real way to prove a chemical reaction is by coming up with a new substance. So physical changes leave you with the same substance (slightly altered in appearance/texture etc.), but chemical reactions give you a new substance.
Do chemical changes produce gas?
Yes, it is correct.
Is making juce is physical changes?
Yes, it is correct.
Why dissolution of NaCl in water is a physical change not a chemical change?
It has been argued whether this is a chemical or physical change. It can be viewed as a chemical change since the Na ion and Cl ion are separated from the crystal lattice, and then become hydrated by water molecules, thus changing the actual chemical structure. However, this is a REVERSIBLE chemical change. Thus, if you evaporate the water, you end up with the same crystalline structure (lattice) that you began with, and so it may now be viewed as simply a physical change. There is no consensus as to which is correct, IMHO.
A physical change is a change in size shape or state of matter?
Yes, that is correct. A physical change is a change in a substance that does not involve changing its chemical composition. This can include changes in size, shape, or state of matter without altering the substance's fundamental makeup.
Physical and chemical changes can be either exothermic or endothermic changes?
The two terms are probably used most often to describe chemical reactions - whether or not they absorb or require heat (endothermic) or create release heat (exothermic). However, since the terms simply mean "absorbing heat", and "giving off heat", they can be used to describe any such event, physical, chemical or nulear. Ray
What is the correct scientific term for a substance that changes colour in this way?
The correct scientific term for a substance that changes color in response to changes in its environment, such as pH or temperature, is "chromophore" or "chromogenic compound." These substances exhibit a reversible change in color due to structural changes in their molecular composition. Common examples include pH indicators and thermochromic materials.
Is it correct to say that chemical changes are not reverisble but phycial changes are?
No, chemical reactions can be reversed. For example: 2H2O -> 2H2 + O2 can change back, 2H2 + O2 -> 2H2O
Is it true that a spontaneous process is a physical or chemical change that occurs with no outside interventions?
That is correct.
How are chemical properties of matter characterized?
Correct characterization of matter chemical properties is possible by experimental studies; but theoretical methods exist for the approximate calculation the values for some chemical and physical properties.
