I only got 50 points (which is not 100). :-)
Look at the graph. At 80 °C, about 38 g of solute is able to dissolve, and that’s for ever 100 g of water. That means that for every 150 grams of water, 57 grams of solute can dissolve (38/2 = 19 + 38 = 57 g) at 80 °C. Since 57 g is greater than 55 g, all for he sodium chloride should dissolve in 150 g of water at 80 °C - you can put all of that into a “mathematical explanation”.
Answer:
A (contains most of the mass of the atom)
Evidence has it that a proton is about 2000 times as massive as an electron.
And there is usually multiple protons and neutrons in the nucleus
From what I just said, you can say that B is wrong
C however is also wrong because protons have a +charge and neutrons are neutrle which means you always have a charge > (greater than) 0
And D is wrong because electrons (which are not in the nucleus) have a neg charge. and protons have a + charge and are in the nucleus
So your answer is A
Hope it helped
Spiky Bob
Answer:
a. +2
b. +3
c. -1
Explanation:
The typical oxidation states can be determined from the periodic table based on the number of valence electrons an atom has.
a. Calcium belongs to group 2A, meaning it has 2 valence electrons and, therefore, would have an oxidation state of +2 in compounds.
b. Aluminum is in group 3A, meaning it has 3 valence electrons and would have an oxidation state of +3 in compounds when the 3 electrons are lost.
c. Fluorine would become fluorine if it gained 1 additional electron to achieve an octet, so its oxidation state would be -1.
Answer:
Answer:
step 1:balance skeleton equation the chemical equation:
Zn +HNO3➔Zn(NO3)2+NO+H2O
step 2: identity undergoing oxidation or reduction
here
Zn➔Zn(NO3)2
Zn is oxidized from 0 to 2 in oxidation no.
HNO3➔NO
N is reduced from 5 to 2 in oxidation no
Step 3: calculate change in oxidation no.
change in oxidation no
in Zn=0-2=-2=2
in
N=5-2=3
Step 4: Balance it by doing crisscrossed multiplication
we get;
3Zn +2HNO3➔3Zn(NO3)2+2NO+H2O
step 6:Balance other atoms except H & O
3Zn +2HNO3➔3Zn(NO3)2+2NO+H2O
3Zn +2HNO3+6HNO3➔3Zn(NO3)2+2NO+H2O
finally: balance H
<em><u>3Zn +8HNO3➔3Zn(NO3)2+2NO+4H2O</u></em>
