The number of protons is always equal to the atomic number of any element. strontium has 38 protons, which when taken away from 90 gives you 52 neutrons, which is three more neutrons than what Sr should have making 38 90Sr an isotope. Hope this helps.
The correct answer is approximately 1.95g. First, take (1.022*10^10)/(1.277*10^9). This is the same as time elapsed/half-life. This gives you 8, which is the number of half lives. Then multiply mass (500.3g) by (1/2)^8, resulting in 1.95g, which is the answer.
1. all elements are made of small particles called atoms
2. atoms of one element are identical in their properties, different atoms from different elements differ in properties
3. chemical reactions consist of atoms rearranging in whole number ratios
4. atoms can not be subdivided, created, or destroyed
Answer:
Explanation:
False. The greater the concentration, the lower the freezing point.
If you mean what F=ma is then it is Force equals mass times acceleration.
