Answer:
A. your observations in writing
Explanation:
Descriptive investigation is one of the mode of inquiries in science. It is devoid of the usual collection of data in the field or setting up laboratory experiments to compared variables.
- In descriptive investigation, observations are usually done in writing.
- They are usually common in Astrology.
- Such investigation involves a question without a hypothesis ensuing.
- Tests are usually not carried out in descriptive investigation.
Answer:
the answer is the tropical rain forest
Answer:
The correct answer is B) it helps to ensure the result are consistent and repeatable.
Explanation:
Scientist generally repeat an experiment if he or she did not make a mistake in the first one to compare the results of two experiment, if there is no difference in the result or values obtainted from the observation of two experiment. he or she become sure that experiment was done in a right way because if there is some error made when experiment was carried out then the result of two same experiment would be different.
Answer:
The mixture is made up of different atoms and pure substance is made up of same type of atom.
The main difference is that mixture can be separated into its component by physical mean while pure substances can not be separated by physical process
Explanation:
Mixture:
- The properties of the mixture are not same and contains the properties of all those component present in it.
- it is a combination of one or more Pure substances and can be separated by simple physical methods.
- it have varying boiling and melting point
Examples are:
- mixture of salt and sand
- Salt water is mixture of water and NaCl and can be separated by physical mean.
- Alloys: its a mixture of different metal
- Air: mixture of gases
Pure Substance:
Pure substances are those made of same type of atoms all elements and compounds are pure substances.
- it can not be separated by simple physical mean
- it have very constant and consistent melting and boiling point
Examples are:
- Water : contain only water molecule
- All elements: all elements are pure substance made of same atoms
- All compounds: can not be separated by physical mean.
Answer:
They are classified as METALS.
Explanation:
Elements are simple substances that cannot be chemically broken down into smaller substances. Based on different characteristics, they are classified into 3 namely:
- metals
- non metals and
- metalloid( mainly act as semi- conductor).
METALS are the type of elements that loses electrons to form positive ion, that is, they are electropositive elements. They are distinguished by the following characteristics:
- LUSTROUS: they have the ability to reflect light from its surface.
- At room temperature: Metals are solid are room temperature with the exception of Mercury which is liquid at room temperature.
- They react and form Basic Compounds
- Great conductor: most metals are great conductors of heat and electricity because they possess free electrons.
- Melting Point: they have high melting points.