Answer:
0.725 kg
Explanation:
Step 1: Given data
- Kinetic energy of the softball (K): 145 J
- Speed of the softball (v): 20.0 m/s
- Mass of the softball (m): ?
Step 2: Calculate the mass of the softball
We will use the following expression.
K = 1/2 × m × v²
m = 2 K / v²
m = 2 × 145 J / (20.0 m/s)²
m = 0.725 kg
The mass of the softball is 0.725 kg.
Answer:
Iron is the densest out of the given options.
Explanation:
Oxygen
1.429 g/L
Water
1000 g/L
Hydrogen Peroxide
1450 g/L
Iron
7874 g/L
Iron Oxide
5240 g/L
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Sodium Oxide= Na2O
The formula mass of Na2O is (2x23) + 16 = 62g/mol
% Na= (46/62) x 100 = 74%
% O= (16/62) x 100 = 26%</span><span>
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Molality is one way of expressing concentration of a solute in a solution. It is expressed as the mole of solute per kilogram of the solvent. To calculate for the molality of the given solution, we need to convert the mass of solute into moles and divide it to the mass of the solvent.
Molality = 29.5 g glucose (1 mol / 180.16 g ) / .950 kg water
Molality = 0.1724 mol / kg
Answer:
The reaction is exothermic
The temperature of the water bath goes up
Explanation:
An exothermic reaction is one in which energy flows out of the reaction system.
In this case, the system is the reaction vessel while the surrounding is the water bath. We see in the question that 300.1J of heat flows out of the system during the reaction. This is heat lost to the surroundings showing that the reaction is exothermic.
As energy is lost to the surroundings, the temperature of the water bath rises accordingly.
