PH stands for "Potential Hydrogen" and the PH scale ranges from 0-14. PH refers to the ability to attract hydrogen ions.
The PH of a solution either indicates acidity of the solution or alkalinity of the solution. A solution which has PH 7 above is a base solution where a solution with PH less than 7 is an acidic solution.
Answer:
- <em><u>Mendeleev produced the first orderly arrangement of known elements.</u></em>
- <em><u>Mendeleev used patterns to predict undiscovered elements.</u></em>
Explanation:
- <u>Mendeleev produced the first orderly arrangement of known elements and used patterns to predict the undiscovered elements.</u>
Those two statments are true.
For the time being there were some 62 known elements. Before Medeleev some schemes to order part of the elements were proposed, but Medeleev showed the relationship between the atomic mass and the properties of the elements (supports second choice). This arrangement is known as the periodic table.
More importantly, Mendeleev predicted correctly the existance and properties of unknown elements, which is his major contribution: he left blanket spaces which where gradually filled when new elements where discovered (this supports the fourth choice).
The first modern chemistry book was written by Antoine Lavoisier (this discards first option).
Mendeleev ordered the elements by increasing mass number (this discards third choice), which was corrected later by the scientist Henry Moseley, who ordered the elements by increasing atomic number (number of protons).
Isotopes were not known by Mendeleev times, so this discards the last option.
Answer:
To answer your question use the code ICE on here to get your answer works every time for me hope this helps
First, we calculate the mass of the sample:
mass = density x volume
mass = 8.48 x 112.5
mass = 954 grams
Now, we will calculate the mass of each component using its percentage mass, then divide it by its atomic mass to find the moles and finally multiply the number of moles by the number of particles in a mole, that is, 6.02 x 10²³.
Zinc mass = 0.37 x 954
Zinc mass = 352.98 g
Zinc moles = 352.98 / 65
Zinc moles = 5.43
Zinc atoms = 5.43 x 6.02 x 10²³
Zinc atoms = 3.27 x 10²⁴
Copper mass = 0.63 x 954
Copper mass = 601.02 g
Copper moles = 601.02 / 64
Copper moles = 9.39
Copper atoms = 9.39 x 6.02 x 10²³
Copper atoms = 5.56 x 10²⁴
Answer:- oxygen.
Explanations:- The electronic configuration is given and we are asked to figure out the electrically neutral atom that will have the electron configuration, 
.
The sum of electrons for this electron configuration is 8. If we look at the periodic table then 8 is the atomic number of oxygen.
So, the electrically neutral atom for the given electron configuration is oxygen.
