Answer:
Explanation:
The following are the order of point from oldest to most recent
1. Atoms are tiny indivisible particles that make up all mater.
it is Postulate of Dalton's atomic theory. this theory was put forward in 1803
2. Negatively charged electrons are embedded in a mass of positive charge.
In 1897 J.J Thomson discovered that atom consist of tiny negatively charged particles called electrons that are uniformly spread in +vely charged matrix this model called as plum pudding model.
3. Atoms consist of mostly empty space with a dense nucleus of positive charge.
While doing experiment on gold foil Rutherford presented a model in 1909 and stated that atom consist mostly empty space with dense nucleus.
4. Electrons occupy specific energy levels surrounding a positively charged nucleus.
Niels Bohr in 1913 put forward a model to explain atomic orbitals/energy level. This is a postulate of Bohr model.
5. Electrons move about a positively charged nucleus in clouds that are defined by probabilities.
In 1926 Erwin Schrödinger explain the wave function of electrons and its probability.
Extensive properties, as volume and mass, depend on the amount of material. So, you can have a sample of gold and a sample of copper with the same volume as long as you have different amount of each one.
On the other hand, intensive properties do not depend on the amound of material but on the chemical constitution of the material. Density is an intensive property, so gold and copper have different densities. That is why you can use intensive properties to characterize different materials.
2H2O --> 2H2 + O2
The mole H2O:mole O2 ratio is 2:1
Now determine how many moles of O2 are in 50g: 50g × 1mol/32g = 1.56 moles O2
Since 1 mole of O2 was produced for every 2 moles of H2O, we need 2×O2moles = H2O moles
2×1.56 = 3.13 moles H2O
Finally, convert moles to grams for H2O:
3.13moles × 18g/mol = 56.28 g H2O
D) 56.28
False
Alkaline is something we use everyday
Acid is something sour eg lemons
Answer:
Nuclear fusion plays an important role in making elements that are heavier than helium.
Explanation:
Nucleosynthesis is the process by which new atomic nuclei are created from pre-existing nucleons (protons and neutrons) and nuclei. According to current theories, the first nuclei were formed a few minutes after the Big Bang, through nuclear reactions in a process called Big Bang nucleosynthesis.
In order to synthesize a new element, there must be a change in the number of protons. We should remember that elements are known by the number of their protons as it represents their atomic number.
Elements heavier than helium are formed by nuclear nucleosynthesis in which nuclear fusion plays a very crucial role as typified by the equations shown in the question.
