Answer: option C. 2 and 3.
Explanation:
1) Isotopes are atoms of a same element with different number of neutrons. That means that the isotopes of a same element have the same number of protons, since the number of protons is what identify an element.
2) For example, all the atoms of oxygen have 8 protons. But isotope oxygen-16 has 8 neutrons, while oxygen-18 has 10 neutrons.
3) In the figure there are 3 different atoms:
i) atom # 1 has 5 protons and 7 neutrons
ii) atom # 2 has 6 protons and 7 neutrons
iii) atom # 3 has 6 protons and 8 neutrons.
4) Hence the atoms with the same number of protons and different number of neutrons are the #2 and the # 3. So, they are the isotopes of the same element.
Answer:
The evidence showing that there is a chemical reaction taking place is the instantaneous temperature drop once the cold pack is shaken.
Explanation:
When an athlete applies a cold pack to the injury, they shake it before, mixing the water and <em>ammonium-nitrate fertilizer</em> inside the cold pack. This mixing is an endothermic reaction, which means it absorbs heat. In turn, the temperature falls to 35 F for around 10 minutes.
Answer:
Igneous rocks must go through the sedimentary process to change into metamorphic rocks. Igneous rocks are chemically changed into metamorphic rocks because of high temperature and pressure. Metamorphic rocks are formed from melting igneous rocks. Metamorphic rocks and igneous rocks do not follow a rock cycle.
Explanation:
hope this helps!
Answer: Molarity of 
in the original sample was 1.96M
Explanation:
Molarity is defined as the number of moles of solute dissolved per liter of the solution.
Now put all the given values in the formula of molarity, we get
Thus molarity of in the original sample was 1.96M
