Compounds are substances made of at least 2 different elements. Molecules have at least 2 atoms, doesn't have to be different elements. Compounds and molecules both work.
Answer:
c. 3.00 M HCl
Explanation:
From dilution formula
C1V1 = C2V2
C1=?, V1= 10.0ml, C= 1.5, V2= 20.0ml
Substitute and Simplify
C1×10= 1.5×20
C1= 3.00M
Answer:
he predicted the properties from known elements above and belws the unknown in the same group
Explanation:
What allowed Mendeleev to make predictions of undiscovered elements
He realized that an element on this table with one known element above it and one known element below it had to have properties between the two known elements
How did Mendeleev predict gallium and germanium?
Based on gaps in the periodic table Mendeleev deduced that in these gaps belonged elements yet to be discovered. Based on other elements below and above in the same group he predicted the existence of eka-aluminum, eka-boron, and eka-silicon, later to be named gallium (Ga), scandium (Sc), and germanium (Ge).
Answer:
C. Organs are made up of cells and tissues.
Explanation:
Answer: when reactants and products are gases at STP.
Justification:
1) STP stands for standard temperature (0°) and pressure (1 atm).
2) According to the kinetic molecular theory of the gases, and as per Avogadro's principle, equal volumes of gases, at the same temperature and pressure, have the same number of molecules.
3) Since the coefficients in a balanced chemical equation represent number of moles, when reactants and products are gases at the same temperature and pressure, the mole ratios are the same that the volume ratios, and then the coefficients of the chemical equation represent the volume ratios.