It would be an physical change ; if you melt butter the butter goes from a solid to a liquid so therefore the physical state is changed.
Answer:
Según el científico inglés John Dalton, los átomos son esferas elásticas e indivisibles. Así, según él, el átomo es el bloque de construcción más pequeño de la materia. Es homogéneo e indivisible, y todos los átomos de un elemento químico dado son idénticos (es decir, tienen el mismo conjunto de propiedades).
Aunque se descubrió a finales del siglo XIX que los átomos están hechos de partículas aún más pequeñas y pueden sufrir transformaciones, y que los átomos de un elemento dado pueden diferir ligeramente entre sí (isótopos), la teoría de Dalton fue la base para el desarrollo de la tecnología química moderna.
In the question, we are told that there are;
- A loaf containing 33 slices
- A loaf containing 33 slices A package of cheese containing 15 slices
We also know that he is making a sandwich that has 2 pieces of both cheese and bread.
Hence;
Total number of bread and cheese = 33 + 15.
Each loaf should have two pieces of each bread and the cheeses make a total of four pieces.
Therefore he can make = 33 + 15/4 = 12 sandwiches.
Answer: C2H2
Explanation: Because each of the lines represent one bond, and because there are three lines (bonds) between the carbons, it means that they are bonded by three bonds, also known as a triple bond.
Half life is the time that it takes for half of the original value of some amount of a radioactive element to decay.
We have the following equation representing the half-life decay:

A is the resulting amount after t time
Ao is the initial amount = 50 mg
t= Elapsed time
t half is the half-life of the substance = 14.3 days
We replace the know values into the equation to have an exponential decay function for a 50mg sample

That would be the answer for a)
To know the P-32 remaining after 84 days we have to replace this value in the equation:

So, after 84 days the P-32 remaining will be 0.85 mg