<span>2 Na + CaF</span>₂<span> = 2 NaF + Ca
is an example of a </span>single- replacement
answer D
hope this helps!
Physical change: a change in which no new substances are formed. the form of the substance is changed but not it's chemical composition (ice melting, bread toasting)
chemical change: any change that results in the formation of new chemical substances. this type of change modifies molecules and atoms by making and breaking the bonds between atoms! (iron rusting, gas burning)
so basically a physical change just changes the appearance of a substance, but a chemical change changes the makeup on a molecular level. i hope this helps you out!
Answer:He 1+
Explanation:
Both Hydrogen atom and helium ion are one electron species. Hence we expect the spectrum of the helium ion to closely resemble that of hydrogen atom also containing one valence electron.
The answer would be Linear. in Carbon Dioxide, the two double bonds count as two pairs of electrons around the carbon atom, predicting linear geometry.
source: http://chemistry.elmhurst.edu/vchembook/207epgeom.html
Answer:
The melting point of this substance at 1 ATM of pressure is 110°.
