Answer:
3 moles
Explanation:
SrCO3
Mass = 442.8g
Molar mass = (87.6 + 12 * [16*3]) = 147.6g/mol
Number of moles = mass / molar mass
Number of moles = 442.8 / 147.6
Number of moles = 3
Answer:
Nitrogen
Explanation:
Elements in period two includes lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine and neon.
According to periodic trends, the electro negativity values are expected to increase across the period up to fluorine. Hence, as we go right wards, we encounter elements with higher electronegative values.
While lithium has an electronegative value of 1 , the electronegative value of element nitrogen is thrrr times this which is equal to three
Opposite pairs form ionic bonds, due to this the answer is D - Li and Br; They have unlike charges.
