Which of the following equations is balanced?
a. na2so4(aq) + cacl2(aq) -> caso4(s) + nacl(aq)
b. na2so4(aq) + cacl2(aq) -> caso4(s) + 2nacl(aq)
c. 2na2so4(aq) + cacl2(aq) -> caso4(s) + 2nacl(aq)
d. na2so4(aq) + 2cacl2(aq) -> caso4(s) +nacl(aq)

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have

Balance and in which category does it fit in? single or double displacement or synthesis or decomposition? (a) k2 o → k + o2 (b) na + i2 → nai (c) cu(no3 )2 + naoh → cu(oh)2 + nano3 (d) kclo3 → kcl + o2 (e) ca(no3 )2 + hbr → cabr2 + hno3 (f) sn(oh)2 → sno + h2 o (g) p4 + n2 o → p4 o6 + n2 (h) fe + al2 (so4 )3 → feso4 + al (i) alcl3 + na2 co3 → al2 (co3 )3 + nacl (j) c3 h6 + o2 → co2 + h2 o

Avariable that is not being directly tested during an experiment should be