Wireless devices, wi-fi routers, granite countertops, microwaves, cigarettes (if you smoke in your house), older box-shaped tv’s, antiques (furniture, jewelry, silverware), smoke detectors ( some use small amounts of radioactive isotope, americium-241 to alert you when there’s smoke in the air, light bulbs, computer screens, electric blankets, garage door openers. Hope it helps.
Answer:
1.63ₓ10⁻⁶ g of U
139.03 g of H
0.385 g of O
141.8 g of Pb
Explanation:
In first place, we need to convert the number of atoms to moles, as we know that 1 mol of anything occupies 6.02×10²³ particles
Therefore:
4.12×10¹⁵ atoms of U . 1 mol / 6.02×10²³ atoms = 6.84×10⁻⁹ moles of U
8.37×10²⁵ atoms of H . 1 mol /6.02×10²³ atoms = 139.03 moles of H
1.45×10²² atoms of O . 1 mol /6.02×10²³ atoms = 0.0241 moles of O
4.12×10²³ atoms of Pb . 1 mol /6.02×10²³ atoms = 0.684 moles of Pb
Moles . Molar mass = Mass (g)
6.84×10⁻⁹ moles of U . 238.03 g/mol = 1.63ₓ10⁻⁶ g of U
139.03 moles of H . 1 g/mol = 139.03 g of H
0.0241 moles of O . 16 g/mol = 0.385 g of O
0.684 moles of Pb . 207.2 g/mol = 141.8 g of Pb
<h3>
Answer:</h3>
1031.4 Calories.
<h3>
Explanation:</h3>
We are given;
Mass of the copper metal = 50.0 g
Initial temperature = 21.0 °C
Final temperature, = 75°C
Change in temperature = 54°C
Specific heat capacity of copper = 0.382 Cal/g°C
We are required to calculate the amount of heat in calories required to raise the temperature of the copper metal;
Quantity of heat is given by the formula,
Q = Mass × specific heat capacity × change in temperature
= 50.0 g × 0.382 Cal/g°C × 54 °C
= 1031.4 Calories
Thus, the amount of heat energy required is 1031.4 Calories.