Answer:
14. the metal is tin which it density is equal 7.3g/cm^3
Answer : The measurements are both precise and accurate.
Explanation :
Accuracy : It is defined as the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 48 kg and another person weighed 55 kg. Then, the weight measured by first person is more accurate.
Precision : It is defined as the closeness of two or more measurements to each other.
For Example: If you weigh a given substance five times and you get 1.8 kg each time. Then the measurement is said to be precise.
Level of precision is determined by the maximum number of decimal places.
When the level of precision is very very less, the measurement can be considered as most precise and most accurate.
As we are given the standard value of the sample is 20.000 and the values measured by the balance are, 19.995, 20.005, 20.001.
Since these three values are in the range of +/- 0.005 from one another. So, we can say that the measurements are both precise and accurate.
Hence, the measurements are both precise and accurate.
Answer:
All description is given in explanation.
Explanation:
Van der Waals forces:
It is the general term used to describe the attraction or repulsion between the molecules. Vander waals force consist of two types of forces:
1. London dispersion forces
2. Dipole-dipole forces
1. London dispersion forces:
These are the weakest intermolecular forces. These are the temporary because when the electrons of atoms come close together they create temporary dipole, one end of an atom where the electronic density is high is create negative pole while the other becomes positive . These forces are also called induce dipole- induce dipole interaction.
2. Dipole-dipole forces:
These are attractive forces , present between the molecules that are permanently polar. They are present between the positive end of one polar molecules and the negative end of the other polar molecule.
Hydrogen bonding:
It is the electrostatic attraction present between the atoms which are chemically bonded. The one atom is hydrogen while the other electronegative atoms are oxygen, nitrogen or flourine. This is weaker than covalent and ionic bond.
Ionic bond or electrostatic attraction:
It is the electrostatic attraction present between the oppositely charged ions. This is formed when an atom loses its electron and create positive charge and other atom accept its electron and create negative charge.
Hydrophobic interaction:
It is the interaction between the water and hydrophobic material. The hydrophobic materials are long chain carbon containing compound. These or insoluble in water.
Covalent bond:
These compounds are formed by the sharing of electrons between the atoms of same elements are between the different element's atoms. The covalent bond is less stronger than ionic bond so require less energy to break as compared to the energy require to break the ionic bond.
Answer:
A decomposition reaction
Explanation:
It is a decomposition reaction where a single type of chemical compound breaks down into two or more elements or new compounds.
Answer: Radioactive waste
Explanation:
The nuclear fission reaction consists of heavy atomic particles or heavy nucleus, like plutonium and uranium and in radioactive heavy metals. In the fission reaction the nucleus get split into equal masses of particles. This process is associated with release of large amount of energy. The fission of radioactive waste can cause deadly mutations in living beings.
