Answer:
Q = -14322.77 J
Explanation:
Given data:
Mass of water = 55.0 g
Initial temperature = 87.3°C
Final temperature = 25.0 °C
Heat given off = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Specific heat capacity of water is 4.18 J/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 25.0 °C - 87.3°C
ΔT = - 62.3 °C
Q = 55.0 g×4.18 J/g.°C × - 62.3 °C
Q = -14322.77 J
We know that the electron clouds of two atoms overlapping is a bond, because that signifies that the electrons are being shared in a bond.
So, I'm going to go through some definitions of these different types of bonds, because they have very specific circumstances.
<u>A hydrogen bond is a bond between an electronegative atom and a hydrogen molecule</u> (which is not what this question says, this isn't stated anywhere).
<u>A dipole is a difference in electron density on two different atoms</u> (so this isn't even close to what the question is stating, a dipole is not even a bond)
<u>An ionic bond is an </u><u><em>unequal sharing of electrons</em></u><u> between two atoms </u>(because the question doesn't state this specific fact, then it can't be this option).
By process of elimination, we know the answer is covalent bond, but just in case, we can also look at the definition of a covalent bond: <u>a bond that involves the sharing of electrons between atoms.</u>
That is exactly what the question is asking for! Therefore, your answer is d. covalent bond
Answer:
The correct answer is 930 grams platelets.
Explanation:
The volume of blood given is 1.89 pints. Total number of gallons in 1.89 pints is,
= 1.89/8 = 0.236 gallon
1 gallon comprise = 3.785 L
So, 0.236 gallon comprise = 0.236 * 3.785 L = 0.89 L
As mentioned that 1 Liter of blood comprise 1.04 kilograms of platelets. Therefore, 0.89 L of blood will contain = 1.04 * 0.89 = 0.93 Kg platelets
1 Kg contain 1000 grams. So, number of platelets in grams will be,
= 1000 * 0.93 = 930 grams platelets.
Answer:
Lithium oxide, Li₂O.
Explanation:
Hello!
In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:
Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:
Thus, we perform the operations in order to obtain:
So we solve for x as shown below:
Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
Best regards!
Answer:
False
Explanation:
When weak bases dissociate, an equilibrium is established rather than dissociating 100%. So OH- and metal ions are partially ionized.
