We have that energy=specific heat * change in temperature * mass. Thus, we have the final temperature (22) minus the initial temperature (55) to equal -33 as our change in temperature. Our specific heat is in J/g*C, so we're good with that because g stands for grams and the aluminium is measured in grams. As there are 10 grams of aluminum, we have
as our final temperature
An exothermic reaction would release energy and would therefore lose heat itself, while an endothermic reaction would absorb energy and gain heat. Therefore, losing heat would be an exothermic reaction
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Answer:The atom being mostly empty space. A small number of alpha particles were deflected by large angles (> 4°) as they passed through the foil. There is a concentration of positive charge in the atom. Like charges repel, so the positive alpha particles were being repelled by positive charge
Answer:
C. The mass of an electron is much less than the mass of a proton or
a neutron.
Explanation:
When we compare the mass of an electron to that of proton or neutron, the mass of an electron is much less than the mass of a proton or a neutron.
Electrons are negatively charged particles in an atom
Protons are positively charged particles
Neutrons do not carry any charges.
- The relative mass of an electron compared to that of a proton is
- This is a very small value
- Electrons generally have mass of 9.11 x 10⁻³¹kg
- Protons weigh 1.67 x 10⁻²⁷kg
- Neutrons weigh 1.68 x 10⁻²⁷kg
We can see that electrons have very small mass and this is why when calculating the mass of an atom, we use the sum of the number of protons and neutrons.
Answer:
Excited state of an electron is the state attained by an electron after it has absorbed energy and it moves further from the nucleus.
an electron is at higher energy when excited and at lower energy when at ground state.
an excited electron is less stable due to the decrease in the nuclear force of attraction and the grounded electron is more stable due to it's close distance to the nucleus.
PbH4 will be formed as a result of a polar covalent bond between the H and the Pb.
Since H is more electronegative than the Pb, it is, thus, expected that the H would be able to pull the electron charge towards itself. This will result in the H being negative.
Based on this:
PbH4 would be expected to <span>have polar covalent bonds with a partial negative charges on the H atoms. </span>
