<u><em>Answer:</em></u>
It was a positive ion.
<u><em>Explanation</em></u>
In CaBr, ionic bond is present. When one of the atom loses electrons and gets positive charges and other atom gains electrons and become negative. As a result of positive and nagative charges , a ionic bond formed.
As in this case, Ca loses electrons and become positive ion while on the other hand bromide gets the electrons and become negative ion.
<em>Note:</em>
Electropositive atoms always loose electrons Like Ca while electronegative atoms always gain elelctrons like Br.
<h2>
Answer:</h2>
- Cu(s) + 2AgNO3(aq) → Cu(NO3)2(aq) + 2Ag(s).
<u>Moles Cu present</u> = 100g Cu x 1 mol Cu/63.55g
= 1.574moles Cu
<u>Mass of Ag produced</u> = 1.574mol Cu x 2mol Ag / 1mol Cu x 107.9g Ag/mol Ag
= 340.g Ag
Answer:
a) 0.03050 = 3.050 × 10-²
b) 0.256 x 10°= 2.56 × 10-¹
c) 25.005 10 = 2.500510 × 10¹
Explanation:
Scientific notations is a way of making very large or very small numbers more comprehensive or simplified. It involves the use of power of ten (10^). The numbers are represented to the power of ten. The following format is used:
a x 10^b
where; a is a number or decimal number between 1 and 10 i.e less than 10 but greater than 1
b is the power of ten
To write a number in scientific notation,
- we move the decimal point right or left depending on whether we're trying to reduce or increase the number
- we count the number of times the decimal point was moved. This serves as the b in the format above.
For example,
a) 0.03050 = 3.050 × 10-²
The decimal point was moved rightward twice. This caused the ^-2 power.
b) 0.256 x 10°= 2.56 × 10-¹
The decimal point was moved rightward once. This caused the ^-1 power.
c) 25.005 10 = 2.500510 × 10¹
The decimal point was moved leftward once. This caused the ^1 power.
Answer:
0.091 mol/L
Explanation:
Molarity of a substance , is the number of moles present in a liter of solution .
M = n / V
M = molarity ( unit = mol / L or M )
V = volume of solution in liter ( unit = L ),
n = moles of solute ( unit = mol ),
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the data of the question , it is given that ,
w = 1.5 g
V = 220 mL
Since ,
1 mL = 1/1000L
V = 0.220 L
As we known , the mass of bleach NaOCl is ,
m = 74.44 g/mol
from the above equation , moles can be calculated as -
n = w / m
n = 1.5g / 74.44 g/mol
n = 0.0201 mol
Molarity of the solution is calculated as ,
M = n / V
M = 0.0201 mol / 0.220 L
M = 0.091 mol/L
The reaction equation:
2H₂O + 2Na₂O₂ → 4NaOH + O₂
Moles of sodium peroxide = 10 / 78 = 0.128
Moles of oxygen released = 0.128 / 2 = 0.064 mol
Mass of oxygen = 0.064 x 32
Mass of oxygen = 2.05 grams
