Answer:
This question is incomplete as it lacks options, the options are:
A) What is the radius of each particle of the substance?
B) Does the substance contain more than one type of atom?
C) Was a chemical reaction necessary to create the substance?
D) What is the electrical charge of the particles of the substance?
The answer is B
Explanation:
In chemistry, an element is a substance made up of a single type of atom i.e. only one atom of the same type constitutes an element while a compound is a substance that contains two or more different elements. If a compound contains different elements, it means that a compound will certainly contain more than one type of atom.
According to this question, the best question to ask when Alyssa wants to differentiate between an element and a compound is: DOES THE SUBSTANCE CONTAIN MORE THAN ONE TYPE OF ATOM?
- If the answer is yes, the substance is a COMPOUND
- If the answer is no, the substance is an ELEMENT.
D) when cells are express different genes
Only plants have chloroplast and a cell wall
Answer:
The speed at which the reactants change to products over a given time.
Explanation:
A chemical's <u>reaction rate</u><u> is the change in the concentration of a reactant or a product with time (in moles per second)</u>.
Remember that during a chemical reaction, reactants are converted to products. Or what is the same, products are formed at the expense of reactants. This can be represented:
reactants → products
Therefore,<u> the progress of a reaction can be followed measuring the decrease in concentration of the reactants or the increase in concentration of the products.</u>
According to the temperature and other parameters, the reaction rate can increase or decrease.