Ionic compound consists of a positively charged ion and a negatively charged anion. For example, NaCl. Na (sodium) is a cation (another word for positively charged ion) and Cl (chloride) is a anion (another way for negatively charged ion.)
Molecular compounds consists of only negatively charged ions. For example Br2I is a compound of 2 elements that are negatively charged.
Unlike ionic compounds, molecular compounds consists of two or more negatively charged elements.
Answer:
Mario uses a hot plate to heat a beaker of 50mL of water. He used a thermometer to measure the
temperature of the water. The water in the beaker began to boil when it reached the temperature of
100'C. If Mario completes the same experiment with 25mL of water, what would happen to the boiling
point?
a) The water will not reach a boil.
b) The boiling point of water will increase.
c) The boiling point of water will decrease.
d) The boiling point of water will stay the same.
Explanation:
First, find moles of oxygen gas: (3.01 x10^23 molec.)/(6.02 x10^23) =0.5mol O2
Second, multiply moles by the standard molar volume of a gas at STP:(0.5mol)(22.4L) = 11.2L O2
Answer:
750mmHg
Explanation:
The following data were obtained from the question:
T1 = 127°C = 127 +273 = 400K
T2 = 27°C = 27 +273 = 300K
P1 = 1000mmHg
P2 =?
P1/T1 = P2/T2
1000/400 = P2 /300
Cross multiply
400 x P2 = 1000 x 300
Divide both side by 400
P2 = (1000 x 300)/400
P2 = 750mmHg
Therefore, the new pressure after cooling is 750mmHg
Answer:
a. 7.8*10¹⁴ He⁺⁺ nuclei/s
b. 4000s
c. 7.7*10⁸s
Explanation:
I = 0.250mA = 2.5 * 10⁻³A
Q = 1.0C
1 e- contains 1.60 * 10⁻¹⁹C
But He⁺⁺ Carrie's 2 charge = 2 * 1.60*10⁻¹⁹C = 3.20*10⁻¹⁹C
(A).
No. Of charge per second = current passing through / charge
1 He⁺⁺ = 2.50 * 10⁻⁴ / 3.2*10⁻¹⁹C
1 He⁺⁺ = 7.8 * 10¹⁴ He⁺⁺ nuclei
(B).
I = Q / t
From this equation, we can determine the time it takes to transfer 1.0C
I = 1.0 / 2.5*10⁻⁴ = 4000s
(C).
Time it takes for 1 mol of He⁺⁺ to strike the target =?
Using Avogadro's ratio,
1.0 mole of He = (6.02 * 10²³ ions/mol ) * (1 / 7.81*10¹⁴ He ions)
Note : ions cancel out leaving the value of the answer in mols.
1.0 mol of He = 7.7 * 10⁸s
